Author name code: tomczyk ADS astronomy entries on 2022-09-14 author:"Tomczyk, Steven" ------------------------------------------------------------------------ Title: Magnetoseismology for the solar corona: from 10 Gauss to coronal magnetograms Authors: Yang, Zihao; Gibson, Sarah; He, Jiansen; Del Zanna, Giulio; Tomczyk, Steven; Morton, Richard; McIntosh, Scott; Wang, Linghua; Karak, Bidya Binay; Samanta, Tanmoy; Tian, Hui; Chen, Yajie; Bethge, Christian; Bai, Xianyong Bibcode: 2022cosp...44.2490Y Altcode: Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the field strengths of oscillating structures in the solar corona. However, previously magnetoseismology was mostly applied to occasionally occurring oscillation events, providing an estimate of only the average field strength or one-dimensional distribution of field strength along an oscillating structure. This restriction could be eliminated if we apply magnetoseismology to the pervasive propagating transverse MHD waves discovered with the Coronal Multi-channel Polarimeter (CoMP). Using several CoMP observations of the Fe XIII 1074.7 nm and 1079.8 nm spectral lines, we obtained maps of the plasma density and wave phase speed in the corona, which allow us to map both the strength and direction of the coronal magnetic field in the plane of sky. We also examined distributions of the electron density and magnetic field strength, and compared their variations with height in the quiet Sun and active regions. Such measurements could provide critical information to advance our understanding of the Sun's magnetism and the magnetic coupling of the whole solar atmosphere. Title: Magnetic Field Measurements in the Large Scale Solar Corona Authors: Tomczyk, S.; Gibson, S. E.; Cosmo Team Bibcode: 2022heli.conf.4031T Altcode: Daily measurements of the magnetic structure of the global solar corona are needed to advance our understanding of critical physical processes. The COSMO 1.5-m Large Coronagraph will enable coronal magnetic field observations. Title: First Images from the Upgraded Coronal Multi-channel Polarimeter (UCoMP) Authors: Tomczyk, Steven; Landi, Enrico; Berkey, Ben; Burkepile, Joan; Cotter, Marc; Gallaher, Dennis; Galloy, Michael D.; Graves, Rob; Oakley, Philip; Perez-Gonzalez, Lisa; Sewell, Scott; de Toma, Giuliana; Zmarzly, Patrick Bibcode: 2021AGUFMSH15G2089T Altcode: The Upgraded Coronal Multi-channel Polarimeter (UCoMP) is a coronal polarimeter with a narrow-band tunable birefringent filter capable of imaging the intensity, full Stokes polarization, and Doppler shift across the coronal emission lines of FeXIV 530.3 nm, FeX 637.4 nm, ArXI 691.8, FeXV 706.2 nm, FeXI 789.4, FeXIII 1074.7 and 1079.8 nm and the chromospheric emission lines of HI 656.3 and HeI 1083 nm. The UCoMP is an upgrade of the CoMP instrument. It has a broader wavelength range (530 - 1083 nm) than CoMP (1074 - 1083 nm) increasing the number of available emission lines in order to observe the corona over a wide range of temperatures, a larger field-of-view (+/- 2 Rsun) compared to CoMP (+/- 1.3 Rsun), and higher spatial resolution (6 arcseconds) compared to CoMP (9 arcseconds). The UCoMP demonstrates the technology of a large aperture (50 mm) tunable birefringent filter based on Lithium Niobate crystals and is a pathfinder instrument for the Coronal Solar Magnetism Observatory. The instrument was shipped to Mauna Loa Solar Observatory in December of 2020, installed in the Spring of 2021, and started taking data May 26, 2021, followed by four months of instrument commissioning. This talk will describe the instrument and present the first images taken with the UCoMP. Title: Magnetoseismology for the solar corona: from 10 Gauss to coronal magnetograms Authors: Yang, Zihao; Bethge, Christian; Tian, Hui; Tomczyk, Steven; Morton, Richard; Del Zanna, Giulio; McIntosh, Scott; Karak, Bidya Binay; Gibson, Sarah; Samanta, Tanmoy; He, Jiansen; Chen, Yajie; Bai, Xianyong; Wang, Linghua Bibcode: 2021AGUFMSH12C..07Y Altcode: Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the field strengths of oscillating structures in the solar corona. However, previously magnetoseismology was mostly applied to occasionally occurring oscillation events, providing an estimate of only the average field strength or one-dimensional distribution of field strength along an oscillating structure. This restriction could be eliminated if we apply magnetoseismology to the pervasive propagating transverse MHD waves discovered with the Coronal Multi-channel Polarimeter (CoMP). Using several CoMP observations of the Fe XIII 1074.7 nm and 1079.8 nm spectral lines, we obtained maps of the plasma density and wave phase speed in the corona, which allow us to map both the strength and direction of the coronal magnetic field in the plane of sky. We also examined distributions of the electron density and magnetic field strength, and compared their variations with height in the quiet Sun and active regions. Such measurements could provide critical information to advance our understanding of the Sun's magnetism and the magnetic coupling of the whole solar atmosphere. Title: The COMPLETE mission concept for the Heliophysics Decadal Survey Authors: Seaton, Daniel; Caspi, Amir; Casini, Roberto; Downs, Cooper; Gibson, Sarah; Gilbert, Holly; Glesener, Lindsay; Guidoni, Silvina; Hughes, Marcus; Reeves, Katharine; Shih, Albert; Tomczyk, Steven; West, Matthew Bibcode: 2021AGUFMSH52A..08S Altcode: We present the COMPLETE mission concept, currently under study for the upcoming Heliophysics Decadal Survey. COMPLETE would provide the first comprehensive measurements of the 3D low-coronal magnetic field and simultaneous 3D energy release diagnostics from large eruptions (flares and CMEs) down to small-scale processes (coronal heating and solar wind outflows). COMPLETE's measurements will finally allow closure on the long-standing question of exactly how energy is stored, released, and transported in impulsive events at all scales. COMPLETE comprises an instrument suite with hard and soft X-ray spectral imagers, gamma-ray and energetic neutral atom spectral imagers, high-resolution wide-field EUV filtergram imagers, photospheric Doppler vector magnetographs, and Hanle-effect UV (Ly-a) coronal magnetographs. Distributed across three spacecraft at the L1, L4, and L5 Earth-Sun Lagrange points, the suite on each spacecraft is optimized for the measurements from that vantage point and for the mission as a whole. Data from all instruments will be processed to enable systems-level analysis from the entire observatory. COMPLETE instrument suite is deliberately complementary across its individual spacecraft, with overlapping fields of view and optimized capabilities to provide a zone of ideal coverage near the west limb as viewed from Earth. Within this region COMPLETE provides comprehensive observations of 3D structures, photospheric and coronal magnetic fields, and signatures of impulsive energy release within integrated data products. The COMPLETE mission concept, and the science and data analysis techniques it espouses, represent a strategic shift from the nearly ubiquitous current practices of siloed study in isolated subdisciplines to a comprehensive, unified systems approach to solar, coronal, and heliophysics. Title: Calibration of a Visible-Light Prototype for the CORSAIR Polarimeter Authors: Bruce, Sarah; Samra, Jenna; Cheimets, Peter; Tomczyk, Steven; Kramar, Maxim Bibcode: 2021AGUFMSH55B1838B Altcode: The coronal magnetic field creates the structure of the corona and is the source of heat and energy for CMEs & solar flares. Studying the polarized light emitted by the corona allows for a better understanding of the coronal magnetic field, which produces measurable signals in the linear & circular polarization through the saturated Hanle effect and the Zeeman effect. These signals are difficult to measure because they are 10 to 10,000 times weaker than the intensity. The Coronal Spectropolarimeter for Airborne Infrared Research (CORSAIR) is a coronagraph, polarimeter, and grating spectrometer that provides two-dimensional spectropolarimetric imaging up to one solar radius from the limb. It is designed to measure the solar coronas full polarization state integrated along the line of sight. The CORSAIR polarimeter comprises a rotating wave plate followed by a fixed linear polarizer (analyzer). The multi-order wave plate provides high polarimetric efficiency across five lines with wavelengths from 1-4 microns. In order to establish a calibration scheme for the CORSAIR polarimeter and explore the issues related to using a multi-order wave plate, we have prototyped the polarimeter in visible light. The prototype operates at 532 nm and 670 nm with a wave plate retardance of just over 17 waves and 13 waves, similar to the retardance of the IR wave plate at 1074.7 nm (Fe XIII) and 1430.5 nm (Si X). The prototyped calibration unit consists of a linear polarizer and a rotating quarter wave plate (QWP) at each wavelength. The polarimeter is calibrated by rotating the QWP 180 degrees for each rotation angle of the polarimeter wave plate, producing a set of modulation and demodulation matrices and associated efficiencies. Due to manufacturing imperfections and other real-world effects, we see small differences between the calibrated and modeled modulation matrices, which have the potential to completely change the resulting linear and circular polarization. We use a model of the full coronal polarization state to explore the effect of polarimeter calibration on the measured linear and circular polarization and define the required calibration accuracy for the IR polarimeter. This work is supported by the NSF-REU Solar Physics program at SAO, grant number AGS-1850750, & the CORSAIR contract, grant number 80NSSC21K0809 from NASA to SAO. Title: Understanding the coronal origins of global heliospheric phenomena through 3D measurements with COMPLETE Authors: Caspi, Amir; Seaton, Daniel; Casini, Roberto; Downs, Cooper; Gibson, Sarah; Gilbert, Holly; Glesener, Lindsay; Guidoni, Silvina; Hughes, Marcus; Reeves, Katharine; Shih, Albert; Tomczyk, Steven; West, Matthew Bibcode: 2021AGUFMSH25F2151C Altcode: Impulsive solar eruptions (flares, coronal mass ejections) and more gradual energetic processes (coronal heating in active regions, solar wind outflows) are powered and governed by the Sun's complex coronal magnetic field. The evolution of these events in the low and middle corona has direct impact on global scales throughout the corona and heliosphere, including as drivers of space weather that affect human and technological assets, but a coherent understanding of globally connected behavior necessarily requires understanding its origins at the Sun. Despite many decades of research, it is still poorly understood exactly how magnetic energy is stored and impulsively released to power plasma heating, particle acceleration, and bulk flows. Breakthroughs have been hindered by two critical limitations: lack of knowledge of the 3D coronal magnetic field and its evolution, and a similar lack of insight into how localized energy release manifests and propagates within 3D coronal structures. Transformative progress to close these gaps requires systematic observations from multiple viewpoints, in a variety of wavelengths, and including coronal magnetometry. Recent and ongoing technological advancements allow us to realize these goals within a decadal timescale. To that end, we present the COMPLETE mission concept, currently under study for the upcoming Heliophysics Decadal Survey. COMPLETEs highly co-optimized and complementary instrument suite include spectroscopic imagers for X-rays, gamma-rays, and energetic neutral atoms; high-resolution wide-field EUV filtergram imagers; photospheric Doppler vector mangetographs; and Hanle-effect UV (Lyman-alpha) coronal magnetographs. Distributed across three spacecraft at the L1, L4, and L5 Earth-Sun Lagrange points, COMPLETE would provide the first comprehensive measurements of the 3D low- and middle-coronal magnetic field and simultaneous 3D energy-release diagnostics from large eruptions down to small-scale processes. COMPLETE represents a strategic shift towards a comprehensive, unified systems approach to solar, coronal, and heliospheric physics, to enable us to finally close decades-old questions of how the Suns magnetic field and impulsive energy release are interrelated, from local to global scales. Title: Mapping the global magnetic field in the solar corona through magnetoseismology Authors: Yang, Zihao; Bethge, Christian; Tian, Hui; Tomczyk, Steven; Morton, Richard; Del Zanna, Giulio; McIntosh, Scott; Karak, Bidya Binay; Gibson, Sarah; Samanta, Tanmoy; He, Jiansen; Chen, Yajie; Wang, Linghua; Bai, Xianyong Bibcode: 2021EGUGA..23..642Y Altcode: Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the field strengths of oscillating structures in the solar corona. However, previously magnetoseismology was mostly applied to occasionally occurring oscillation events, providing an estimate of only the average field strength or one-dimensional distribution of field strength along an oscillating structure. This restriction could be eliminated if we apply magnetoseismology to the pervasive propagating transverse MHD waves discovered with the Coronal Multi-channel Polarimeter (CoMP). Using several CoMP observations of the Fe XIII 1074.7 nm and 1079.8 nm spectral lines, we obtained maps of the plasma density and wave phase speed in the corona, which allow us to map both the strength and direction of the coronal magnetic field in the plane of sky. We also examined distributions of the electron density and magnetic field strength, and compared their variations with height in the quiet Sun and active regions. Such measurements could provide critical information to advance our understanding of the Sun's magnetism and the magnetic coupling of the whole solar atmosphere. Title: Electron Densities in the Solar Corona Measured Simultaneously in the Extreme Ultraviolet and Infrared Authors: Dudík, Jaroslav; Del Zanna, Giulio; Rybák, Ján; Lörinčík, Juraj; Dzifčáková, Elena; Mason, Helen E.; Tomczyk, Steven; Galloy, Michael Bibcode: 2021ApJ...906..118D Altcode: 2020arXiv201109175D Accurate measurements of electron density are critical for determination of the plasma properties in the solar corona. We compare the electron densities diagnosed from Fe XIII lines observed by the Extreme-Ultraviolet Imaging Spectrometer (EIS) onboard the Hinode mission with the near-infrared (NIR) measurements provided by the ground-based Coronal Multichannel Polarimeter (CoMP). To do that, the emissivity-ratio method based on all available observed lines of Fe XIII is used for both EIS and CoMP. The EIS diagnostics is further supplemented by the results from Fe XII lines. We find excellent agreement, within 10%, between the electron densities measured from both extreme-ultraviolet and NIR lines. In the five regions selected for detailed analysis, we obtain electron densities of log(Ne [cm-3]) = 8.2-8.6. Where available, the background subtraction has a significant impact on the diagnostics, especially on the NIR lines, where the loop contributes less than a quarter of the intensity measured along the line of sight. For the NIR lines, we find that the line center intensities are not affected by stray light within the instrument, and recommend using these for density diagnostics. The measurements of the Fe XIII NIR lines represent a viable method for density diagnostics using ground-based instrumentation. Title: Coronagraphy from the Ground: Current and Future Observations Authors: Burkepile, J.; Tomczyk, S.; Zmarzly, P.; de Wijn, A.; Gibson, S. E.; de Toma, G.; Galloy, M. D. Bibcode: 2020AGUFMSH031..03B Altcode: Ground-based coronagraphs provided the first observations of the ethereal corona outside of a total solar eclipse in 1931. Invented by Bernard Lyot, coronagraphs enabled long time-series images and movies of the emission line corona. Advances in technology have led to more sophisticated coronagraphs capable of observing polarized light from spectral lines and the coronal continuum. These observations, coupled with advances in our understanding of resonance scattering-induced polarization, have greatly facilitated our knowledge of coronal physics and explosive events such as Coronal Mass Ejections (CMEs). While space-based coronagraphs provide spectacular observations of the extended corona, ground-based coronagraphs continue to contribute important, unique and complementary inner coronal observations at a fraction of the cost of a space-based mission. We discuss current ground-based solar coronagraphs, observations and data products and highlight future instruments and network capabilities and benefits. Title: Untangling the global coronal magnetic field with multiwavelength observations Authors: Gibson, S. E.; Malanushenko, A.; de Toma, G.; Tomczyk, S.; Reeves, K.; Tian, H.; Yang, Z.; Chen, B.; Fleishman, G.; Gary, D.; Nita, G.; Pillet, V. M.; White, S.; Bąk-Stęślicka, U.; Dalmasse, K.; Kucera, T.; Rachmeler, L. A.; Raouafi, N. E.; Zhao, J. Bibcode: 2020arXiv201209992G Altcode: Magnetism defines the complex and dynamic solar corona. Coronal mass ejections (CMEs) are thought to be caused by stresses, twists, and tangles in coronal magnetic fields that build up energy and ultimately erupt, hurling plasma into interplanetary space. Even the ever-present solar wind possesses a three-dimensional morphology shaped by the global coronal magnetic field, forming geoeffective corotating interaction regions. CME evolution and the structure of the solar wind depend intimately on the coronal magnetic field, so comprehensive observations of the global magnetothermal atmosphere are crucial both for scientific progress and space weather predictions. Although some advances have been made in measuring coronal magnetic fields locally, synoptic measurements of the global coronal magnetic field are not yet available. We conclude that a key goal for 2050 should be comprehensive, ongoing 3D synoptic maps of the global coronal magnetic field. This will require the construction of new telescopes, ground and space-based, to obtain complementary, multiwavelength observations sensitive to the coronal magnetic field. It will also require development of inversion frameworks capable of incorporating multi-wavelength data, and forward analysis tools and simulation testbeds to prioritize and establish observational requirements on the proposed telescopes. Title: Mapping the magnetic field in the solar corona through magnetoseismology Authors: Yang, ZiHao; Tian, Hui; Tomczyk, Steven; Morton, Richard; Bai, XianYong; Samanta, Tanmoy; Chen, YaJie Bibcode: 2020ScChE..63.2357Y Altcode: 2020arXiv200803146Y Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the field strengths of oscillating structures in the solar corona. However, previously magnetoseismology was mostly applied to occasionally occurring oscillation events, providing an estimate of only the average field strength or one-dimensional distribution of field strength along an oscillating structure. This restriction could be eliminated if we apply magnetoseismology to the pervasive propagating transverse MHD waves discovered with the Coronal Multi-channel Polarimeter (CoMP). Using several CoMP observations of the Fe xiii 1074.7 nm and 1079.8 nm spectral lines, we obtained maps of the plasma density and wave phase speed in the corona, which allow us to map both the strength and direction of the coronal magnetic field in the plane of sky. We also examined distributions of the electron density and magnetic field strength, and compared their variations with height in the quiet Sun and active regions. Such measurements could provide critical information to advance our understanding of the Sun's magnetism and the magnetic coupling of the whole solar atmosphere. Title: Global maps of the magnetic field in the solar corona Authors: Yang, Zihao; Bethge, Christian; Tian, Hui; Tomczyk, Steven; Morton, Richard; Del Zanna, Giulio; McIntosh, Scott W.; Karak, Bidya Binay; Gibson, Sarah; Samanta, Tanmoy; He, Jiansen; Chen, Yajie; Wang, Linghua Bibcode: 2020Sci...369..694Y Altcode: 2020arXiv200803136Y Understanding many physical processes in the solar atmosphere requires determination of the magnetic field in each atmospheric layer. However, direct measurements of the magnetic field in the Sun’s corona are difficult to obtain. Using observations with the Coronal Multi-channel Polarimeter, we have determined the spatial distribution of the plasma density in the corona and the phase speed of the prevailing transverse magnetohydrodynamic waves within the plasma. We combined these measurements to map the plane-of-sky component of the global coronal magnetic field. The derived field strengths in the corona, from 1.05 to 1.35 solar radii, are mostly 1 to 4 gauss. Our results demonstrate the capability of imaging spectroscopy in coronal magnetic field diagnostics. Title: A New Facility for Airborne Solar Astronomy: NASA's WB-57 at the 2017 Total Solar Eclipse Authors: Caspi, Amir; Seaton, Daniel B.; Tsang, Constantine C. C.; DeForest, Craig E.; Bryans, Paul; DeLuca, Edward E.; Tomczyk, Steven; Burkepile, Joan T.; Casey, Thomas "Tony"; Collier, John; Darrow, Donald "DD"; Del Rosso, Dominic; Durda, Daniel D.; Gallagher, Peter T.; Golub, Leon; Jacyna, Matthew; Johnson, David "DJ"; Judge, Philip G.; Klemm, Cary "Diddle"; Laurent, Glenn T.; Lewis, Johanna; Mallini, Charles J.; Parent, Thomas "Duster"; Propp, Timothy; Steffl, Andrew J.; Warner, Jeff; West, Matthew J.; Wiseman, John; Yates, Mallory; Zhukov, Andrei N.; NASA WB-57 2017 Eclipse Observing Team Bibcode: 2020ApJ...895..131C Altcode: 2020arXiv200409658C NASA's WB-57 High Altitude Research Program provides a deployable, mobile, and stratospheric platform for scientific research. Airborne platforms are of particular value for making coronal observations during total solar eclipses because of their ability both to follow the Moon's shadow and to get above most of the atmospheric air mass that can interfere with astronomical observations. We used the 2017 August 21 eclipse as a pathfinding mission for high-altitude airborne solar astronomy, using the existing high-speed visible-light and near/midwave infrared imaging suite mounted in the WB-57 nose cone. In this paper, we describe the aircraft, the instrument, and the 2017 mission; operations and data acquisition; and preliminary analysis of data quality from the existing instrument suite. We describe benefits and technical limitations of this platform for solar and other astronomical observations. We present a preliminary analysis of the visible-light data quality and discuss the limiting factors that must be overcome with future instrumentation. We conclude with a discussion of lessons learned from this pathfinding mission and prospects for future research at upcoming eclipses, as well as an evaluation of the capabilities of the WB-57 platform for future solar astronomy and general astronomical observation. Title: Tomographic Measurements of Magnetic Free Energy in CME Source Regions Authors: Lin, H.; Kramar, M.; Tomczyk, S. Bibcode: 2019AGUFMSH53B3378L Altcode: Magnetic free energies (MFEs) contained in highly non-potential coronal magnetic field in active regions are believed to be the primary source of energy of solar eruptions. Recent progresses in observational capabilities and tomographic inversion techniques have allowed us to directly determine the 3D structures of the temperature, density and magnetic fields of the solar corona (Kramar et al., 2016) using space EUV coronal emission line (CEL) data and ground-based synoptic IR CELs polarization observations. The magnetic free energy of the solar corona can now be directly derived from these observationally determined coronal models. We will present measurements of the MFEs at the source regions of coronal mass ejections (CMEs) and comparisons of the MFEs with direct measurements of kinetic energies of the CMEs. These studies will help us understand the energetics of the solar eruptions. Title: Coronal Solar Magnetism Observatory Science Objectives Authors: Gibson, S. E.; Tomczyk, S.; Burkepile, J.; Casini, R.; DeLuca, E.; de Toma, G.; de Wijn, A.; Fan, Y.; Golub, L.; Judge, P. G.; Landi, E.; McIntosh, S. W.; Reeves, K.; Seaton, D. B.; Zhang, J. Bibcode: 2019AGUFMSH11C3395G Altcode: Space-weather forecast capability is held back by our current lack of basic scientific understanding of CME magnetic evolution, and the coronal magnetism that structures and drives the solar wind. Comprehensive observations of the global magnetothermal environment of the solar atmosphere are needed for progress. When fully implemented, the COSMO suite of synoptic ground-based telescopes will provide the community with comprehensive and simultaneous measurements of magnetism, temperature, density and plasma flows and waves from the photosphere through the chromosphere and out into the corona. We will discuss how these observations will uniquely address a set of science objectives that are central to the field of solar and space physics: in particular, to understand the storage and release of magnetic energy, to understand CME dynamics and consequences for shocks, to determine the role of waves in solar atmospheric heating and solar wind acceleration, to understand how the coronal magnetic field relates to the solar dynamo, and to constrain and improve space-weather forecast models. Title: High-Altitude Instrumentation for Infrared Observations of the Solar Corona Authors: Samra, J.; Cheimets, P.; DeLuca, E.; Golub, L.; Hannigan, J. W.; Judge, P. G.; Madsen, C. A.; Marquez, V.; Tañón Reyes, N.; Tomczyk, S. Bibcode: 2019AGUFMSH43B..07S Altcode: High-altitude infrared remote sensing is a promising new method for measuring coronal plasma and magnetic fields. We present new results from a recent airborne eclipse mission and outline concepts for future airborne and balloon-based instruments for coronal spectroscopy and spectro-polarimetry.

The airborne infrared spectrometer (AIR-Spec) was commissioned during the 2017 total solar eclipse, when it observed five infrared coronal emission lines from the NSF Gulfstream V research jet. These magnetically sensitive emission lines of highly ionized magnesium, silicon, sulfur, and iron are promising candidates for future observations of the coronal magnetic field, and their characterization is an important first step toward developing the next generation of instrumentation for coronal magnetometry. The second AIR-Spec research flight took place during the July 2, 2019 total solar eclipse across the south Pacific. Higher sensitivity and reduced jitter enabled more precise measurements of emission line properties and plasma density, temperature, and line-of-sight velocity up to one solar radius from the solar limb. Atmospheric absorption was significant, even at altitude, and atmospheric modeling was required to extract accurate line intensities.

AIR-Spec is a slit spectrometer that measures light over a 1.55 solar radius field of view in three spectral passbands between 1.4 and 3 microns. The successful eclipse missions overcame a number of engineering challenges, centered around maintaining adequate resolution and signal-to-noise ratio in a compact and inexpensive package on a moving platform. AIR-Spec is a pathfinder for future infrared spectrometers and spectro-polarimeters, including a balloon-based coronagraph that will measure the global coronal magnetic field and an airborne spectrometer that will survey the infrared emission corona during a future eclipse. Title: Novel observations of the middle corona during the 2017 total solar eclipse Authors: Caspi, A.; Seaton, D. B.; Tsang, C.; DeForest, C.; Bryans, P.; Samra, J.; DeLuca, E.; Tomczyk, S.; Burkepile, J.; Gallagher, P.; Golub, L.; Judge, P. G.; Laurent, G. T.; West, M.; Zhukov, A. Bibcode: 2019AGUFMSH13A..10C Altcode: Total solar eclipses offer rare opportunities to study the middle corona. This intriguing region contains complex interfaces and transitions between physical regimes, but has historically been under-observed due to the challenges of observing its dim emission so close to the bright inner corona and blinding solar disk. The unique circumstances of a total solar eclipse coupled with a high-altitude observing platform provide nearly space-quality observing conditions, including for wavelengths inaccessible by ground-based observatories, but with availability of ground-quality resources, including high-speed, high-resolution, wide-field coronography typically inaccessible from space. We used the 2017 August 21 "Great American" total solar eclipse to observe the solar corona from ~1.02 to ~3 RSun in both visible (533.9 ± 4.75 nm) and medium-wave infrared (3-5 μm) light using stabilized telescopes on two of NASA's WB-57F high-altitude research aircraft. This pathfinding mission utilized existing instrumentation to evaluate the platform performance, guide instrumentation development, and explore new discovery space for future studies of the middle corona.

We present the high-speed (30 Hz), high-resolution (3 arcsec/pixel) visible and IR observations obtained during the eclipse, and analysis of these observations in the context of coronal structure and dynamics. We discuss the limitations of the prototype data and pathways forward for future instrumentation and missions optimized for the range of observable parameters in the middle corona. We also discuss the benefits of such eclipse studies to an understanding of the corona as a single, unified system, from its origins at the solar surface to its extension into the heliosphere, particularly within the context of a developing multi- and inter-disciplinary research collaboration, COHERENT (the "Corona as a Holistic Environment" Research Network). Title: Solar Eclipse Observations from the Ground and Air from 0.31 to 5.5 Microns Authors: Judge, Philip; Berkey, Ben; Boll, Alyssa; Bryans, Paul; Burkepile, Joan; Cheimets, Peter; DeLuca, Edward; de Toma, Giuliana; Gibson, Keon; Golub, Leon; Hannigan, James; Madsen, Chad; Marquez, Vanessa; Richards, Austin; Samra, Jenna; Sewell, Scott; Tomczyk, Steven; Vera, Alysha Bibcode: 2019SoPh..294..166J Altcode: We present spectra and broad-band polarized light data from a novel suite of instruments deployed during the 21st August 2017 total solar eclipse. Our goals were to survey solar spectra at thermal infrared wavelengths during eclipse, and to test new technology for measuring polarized coronal light. An infrared coronal imaging spectrometer, flown at 14.3 km altitude above Kentucky, was supported on the ground by observations from Madras, Oregon (elevation 683 m) and Camp Wyoba on Casper Mountain, Wyoming (2402 m). In Wyoming we deployed a new infrared Fourier Transform Spectrometer (FTS), three low-dispersion spectrometers loaned to us by Avantes, a novel visible-light camera PolarCam, sensitive to linear polarization, and one of two infrared cameras from FLIR Systems, the other operated at Madras. Circumstances of eclipse demanded that the observations spanned 17:19 to 18:26 UT. We analyze spectra of the limb photosphere, the chromosphere, prominences, and coronal lines from 310 nm to 5.5 μm. We calibrated data photometrically using the solar disk as a source. Between different spectrometers, the calibrations were consistent to better than 13%. But the sensitivities achieved were insufficient to detect coronal lines from the ground. The PolarCam data are in remarkable agreement with polarization data from the K-Cor synoptic instrument on Mauna Loa, and with FLIR intensity data acquired in Madras. We discuss new results, including a detection of the He I 1083 nm multiplet in emission during the whole of totality. The combination of the FTS and AIR-Spec spectra reveals for the first time the effects of the telluric extinction on the infrared coronal emission lines, to be observed with upcoming Daniel K. Inouye Solar Telescope. Title: Investigating Coronal Magnetism with COSMO: Science on the Critical Path To Understanding The ``Weather'' of Stars and Stellarspheres Authors: McIntosh, Scott; Tomczyk, Steven; Gibson, Sarah E.; Burkepile, Joan; de Wijn, Alfred; Fan, Yuhong; deToma, Giuliana; Casini, Roberto; Landi, Enrico; Zhang, Jie; DeLuca, Edward E.; Reeves, Katharine K.; Golub, Leon; Raymond, John; Seaton, Daniel B.; Lin, Haosheng Bibcode: 2019BAAS...51g.165M Altcode: 2019astro2020U.165M The Coronal Solar Magnetism Observatory (COSMO) is a unique ground-based facility designed to address the shortfall in our capability to measure magnetic fields in the solar corona. Title: Upgraded Coronal Multi-channel Polarimeter (UCoMP) Authors: Tomczyk, Steven; Landi, Enrico Bibcode: 2019shin.confE.131T Altcode: The Coronal Multi-channel Polarimeter (CoMP) is a coronal polarimeter with a narrow-band tunable Lyot filter capable of imaging the intensity, polarization and Doppler shift in the coronal emission lines of FeXIII 1074.7 and 1079.8 nm and HeI 1083 nm. We are currently in the process of upgrading the CoMP instrument to 1) broaden the wavelength range to 530 - 1083 nm to increase of emission lines that can be observed to 9 in order to enhance the plasma diagnostic capabilities of the CoMP, 2) increase the field-of-view to 1 degree, and 3) increase the spatial resolution. This poster will describe the upgrade and focus on the enhanced scientific capabilities of the UCoMP. The UCoMP will be deployed in September of 2019. Title: High-cadence Visible and Infrared Spectra of the Sun during Eclipse Authors: Judge, P.; Tomczyk, S.; Hannigan, J.; Sewell, S. Bibcode: 2019ApJ...877...10J Altcode: We study novel spectra from 310 nm to 5.5 μm obtained during the 2017 August 21 eclipse. Four spectrometers were deployed at Camp Wyoba (altitude 2402 m) on Casper Mountain, WY. Three low-resolution ({ \mathcal R } ≲ 1000) Avantes spectrometers obtained useful spectra from 310 nm to 2.3 μm, at cadences from 8 to 500 ms. To maximize photometric precision, these instruments were fed with optical fibers placed in the pupil planes of two small (D = 5 cm) telescopes, thereby integrating all light from the field of view. We also acquired higher-resolution ({ \mathcal R } ≈ 30000) spectra with a new infrared Fourier Transform Spectrometer, fed by a Sun-tracking heliostat, at a 2.5 s cadence. We calibrate the fluxes using counts obtained during partial eclipse, with known limb-darkened photospheric intensities. Fluxes of chromospheric lines, including Ca II H, K, and Hα, obtained near third contact, were measured every 20 ms, a sampling in height above the limb of 5.6 km. The behavior found corresponds to that found in traditional (image-plane) flash spectra. Two unknown chromospheric emission lines are noted. Based upon our measurements and earlier calculations, we propose new eclipse experiments to uncover clues to the origin and structure of spicules. Title: COSMO Science Authors: Gibson, Sarah; Tomczyk, Steven; Burkepile, Joan; Casini, Roberto; Deluca, Ed; de Toma, Giuliana; deWijn, Alfred; Fan, Yuhong; Golub, Leon; Judge, Philip; Landi, Enrico; Lin, Haosheng; McIntosh, Scott; Reeves, Kathy; Seaton, Dan; Zhang, Jie Bibcode: 2019shin.confE..32G Altcode: Space-weather forecast capability is held back by our current lack of basic scientific understanding of CME magnetic evolution, and the coronal magnetism that structures and drives the solar wind. Comprehensive observations of the global magnetothermal environment of the solar atmosphere are needed for progress. When fully implemented, the COSMO suite of synoptic ground-based telescopes will provide the community with comprehensive and simultaneous measurements of magnetism, temperature, density and plasma flows and waves from the photosphere through the chromosphere and out into the corona. We will discuss how these observations will uniquely address a set of science objectives that are central to the field of solar and space physics: in particular, to understand the storage and release of magnetic energy, to understand CME dynamics and consequences for shocks, to determine the role of waves in solar atmospheric heating and solar wind acceleration, to understand how the coronal magnetic field relates to the solar dynamo, and to constrain and improve space-weather forecast models. Title: Investigating Coronal Magnetism with COSMO: Science on the Critical Path To Understanding The "Weather" of Stars and Stellarspheres Authors: McIntosh, Scott; Tomczyk, Steven Bibcode: 2019BAAS...51c.407M Altcode: 2019astro2020T.407M The white paper discusses the measurement of coronal magnetism as a gateway to improving our understanding of the heliosphere, drive improvements in space weather and ultimately understanding stellar coronae and stellar weather. Title: Experimental Testing of Scattering Polarization Models Authors: Li, W.; Casini, R.; Tomczyk, S.; Landi Degl'Innocenti, E.; Marsell, B. Bibcode: 2018ApJ...867L..22L Altcode: 2018arXiv181107090L We realized a laboratory experiment to study the scattering polarization of the Na I D-doublet at 589.0 and 589.6 nm in the presence of a magnetic field. This work was stimulated by solar observations of that doublet, which have proven particularly challenging to explain through available models of polarized line formation, even to the point of casting doubts on our very understanding of the underlying physics. The purpose of the experiment was to test a quantum theory for the polarized scattering of spectrally flat incident radiation, on which much of the current magnetic diagnostics of stellar atmospheres is based. The experiment has confirmed the predictions of that theory, and its adequacy for the modeling of scattering polarization under flat-spectrum illumination. Title: The Coronal Solar Magnetism Observatory Authors: Thompson, Michael J.; Tomczyk, Steven; Gibson, Sarah E.; McIntosh, Scott W.; Landi, Enrico Bibcode: 2018IAUS..335..359T Altcode: The Coronal Solar Magnetism Observatory (CoSMO) is a proposed new facility led by the High Altitude Observatory and a consortium of partners to measure magnetic field and plasma properties in a large (one degree) field of view extending down to the inner parts of the solar corona. CoSMO is intended as a research facility that will advance the understanding and prediction of space weather. The instrumentation elements of CoSMO are: a white-light coronagraph (KCor), already operational at the Mauna Loa Solar Observatory (MLSO); the Chromosphere and Prominence Magnetometer (ChroMag), due for deployment to MLSO next year; and the CoSMO Large Coronagraph (LC) which has completed Preliminary Design Review. Title: The eruption of a prominence carrying coronal flux rope: forward synthesis of the magnetic field strength measurement by the COronal Solar Magnetism Observatory Large Coronagraph Authors: Fan, Yuhong; Gibson, Sarah; Tomczyk, Steven Bibcode: 2018cosp...42E1038F Altcode: From a magnetohydrodynamic (MHD) simulation of the eruption of prominence hosting coronal flux rope, we carry out forward synthesis of the circular polarization signal V/I produced by the MHD model as measured by the proposed COronal Solar Magnetism Observatory (COSMO) Large Coronagraph (LC) and infer the line-of-sight magnetic field BLOS above the limb. With an aperture of 150 cm, integration time of 300 sec, and an observation pixel of 12 arcsec, the LC can measure a significant BLOS with sufficient signal to noise level, from the simulated flux rope with a peak azimuthal field strength of about 10 G. The measured BLOS is found to relate well with the axial field strength of the flux rope within the height range of the prominence, and can discern the increase with height of the magnetic field strength along the prominence that is a definitive signature of the concave upturning dipped field supporting the prominence. The measurement can also detect above the noise the outward rise of the BLOS due to the slow rise of the flux rope as it develops the kink instability, during the phase when its rise speed is still below 15 km/s and up to a height of about 1.25 solar radius. These results suggest that the COSMO LC has great potential in providing quantitative information about the magnetic field structure of CME precursors (such as prominences) and their early evolution for the onset of eruption. Title: The coronal magnetic field derived by vector tomography from IR and UV measurements Authors: Kramar, Maxim; Tomczyk, Steven; Lin, Haosheng Bibcode: 2018cosp...42E1830K Altcode: One of the major problems in solar physics is to measure the coronal magnetic fields before and during the coronal transients events. Spectropolarimetric coronal observations of magnetically sensitive spectral lines provide an information about the magnetic field. However, inversion of the magnetic field from such types of measurements is not straightforward due to the nature of the line formation mechanisms and the fact that the coronal is optically thin. Because of the latter it is generally not possible to spatially resolve the coronal field over the line of sight (LOS). Tomography, i.e. observations form multiple LOSe, is required. We applied the vector tomography technique to measurements of the Fe XIII 10747 A Hanle effect linear polarization obtained by the Coronal Multichannel Polarimeter (CoMP). The photospheric observations and divergenceless of the field were used as additional constraints in the tomographic inversion. The inversion method also requires to know the 3D distribution of the coronal electron density and temperature which have been reconstructed by scalar field tomography based on STEREO/EUVI data. The obtained 3D coronal magnetic field has been validated by relating its structures (streamers, pseudostreamers, coronal holes) to the STEREO/EUVI images and to the global 3D coronal electron density obtained by tomography based on STEREO/COR1 data. Also, we explore how the inclusion of circular polarization IR measurements of the coronal Zeeman effect (together with the linear polarization measurements of the Hanle effect) into the inversion will affect the quality of the magnetic field reconstruction. Title: New Coronal Science from NASA WB-57F High-Altitude Aircraft Observations of the 2017 Total Solar Eclipse Authors: Caspi, Amir; DeLuca, . Edward; Tomczyk, Steven; DeForest, Craig; Bryans, Paul; Seaton, Daniel; Tsang, Constantine Bibcode: 2018cosp...42E.526C Altcode: Total solar eclipses present rare opportunities to study the complex solar corona, down to altitudes of just a few percent of a solar radius above the surface, using ground-based and airborne observatories that would otherwise be dominated by the intense solar disk and high sky brightness. Studying the corona is critical to gaining a better understanding of physical processes that occur on other stars and astrophysical objects, as well as understanding the dominant driver of space weather that affects human assets at Earth and elsewhere. For example, it is still poorly understood how the corona is heated to temperatures of 1-2 MK globally and up to 5-10 MK above active regions, while the underlying chromosphere is 100 times cooler; numerous theories abound, but are difficult to constrain due to the limited sensitivities and cadences of prior measurements. The stability of large-scale coronal structures and the extent of their reach to the middle and outer corona are also not well known, limited in large part by sensitivities and fields of view of existing observations.Airborne observations during a total eclipse provide unique advantages. By flying in the stratosphere at altitudes of 50 kft or higher, they avoid all weather, the seeing quality is enormously improved, and additional wavelengths such as near-IR also become available due to significantly reduced water absorption. An airborne observatory can also follow the Moon's shadow, increasing the total observing time by 50% or more.We present current results of solar coronal measurements from airborne observations of the 2017 Great American Total Solar Eclipse using two of NASA's WB-57 high-altitude research aircraft, each equipped with two 8.7" telescopes feeding high-sensitivity visible (green line and nearby continuum) and medium-wave IR (3-5 {μ}m) cameras operating at high cadence (30 Hz) with ∼3 arcsec/pixel platescale and ±3 R_{sun} fields of view. The aircraft flew along the eclipse path, separated by ∼110 km, to observe a summed ∼7.5 minutes of totality in both visible and MWIR. These observations enable groundbreaking studies of high-speed coherent motion - including possible Alfvén waves and nanojets - in the lower and middle corona that could shed light on coronal heating processes and the formation and stability of coronal structures. Our MWIR observations of a cool prominence and hot coronal active region plasma will be combined with spectra from the AIR-Spec instrument, flown concurrently on NCAR's HIAPER GV. We review the WB-57 eclipse mission and the current results of analysis on the visible and IR coronal measurements, along with an outlook for future analysis and missions. Title: Turbulence and Heating in the Flank and Wake Regions of a Coronal Mass Ejection Authors: He, Jiansen; Song, Hong-Qiang; Tomczyk, Steven; Wang, Linghua; Tian, Hui; Fan, Siteng; Zhang, Lei; Yan, Limei Bibcode: 2018cosp...42E1404H Altcode: As a coronal mass ejection (CME) passes, the flank and wake regions are typically strongly disturbed. Various instruments, including the Large Angle and Spectroscopic Coronagraph (LASCO), the Atmospheric Imaging Assembly (AIA), and the Coronal Multi-channel Polarimeter (CoMP), observed a CME close to the east limb on 26 October 2013.A hot (∼10 MK) rising blob was detected on the east limb, with an initial ejection flow speed of ∼330 km/s. The magnetic structures on both sides and in the wake of the CME were strongly distorted, showing initiation of turbulent motions with Doppler-shift oscillations enhanced from ∼ ±3 km/s to ∼ ±15 km/s and effective thermal velocities from ∼30 km/s to ∼60 km/s, according to the CoMP observations at the Fe XIII line. The CoMP Doppler-shift maps suggest that the turbulence behaved differently at various heights; it showed clear wave-like torsional oscillations at lower altitudes, which are interpreted as the anti-phase oscillation of an alternating red/blue Doppler shift across the strands at the flank. The turbulence seems to appear differently in the channels of different temperatures. Its turnover time was ∼1000 seconds for the Fe 171 Å channel, while it was ∼500 seconds for the Fe 193 Å channel. Mainly horizontal swaying rotations were observed in the Fe 171 Å channel, while more vertical vortices were seen in the Fe 193 Å channel. The differential-emission-measure profiles in the flank and wake regions have two components that evolve differently: the cool component decreased over time, evidently indicating a drop-out of cool materials due to ejection, while the hot component increased dramatically,probably because of the heating process, which is suspected to be a result of magnetic reconnection and turbulence dissipation. These results suggest a new turbulence-heating scenario of the solar corona and solar wind. Title: A Space Coronal Magnetometry Mission Authors: Lin, Haosheng; Gibson, Sarah; Savage, Sabrina; Tomczyk, Steven; Downs, Cooper; Rachmeler, Laurel; Kramar, Maxim; Habbal, Shadia Bibcode: 2018cosp...42E2020L Altcode: Direct measurement of the polarized spectra of forbidden coronal emission lines (CELs) is the most powerful tool for the study of the solar coronal magnetic fields. Due to its low optical density, simultaneous multi-sight-lines observations of the corona from space are needed for tomographic inversion to disentangle the 3D structure of the solar corona. This presentation will describe the mission concept and instrument design of a future space coronal magnetometry mission, consists of many clusters of small spacecraft in near-sun heliocentric orbits to observe the sun to enable tomographic determination of the 3D magnetic and thermodynamic structures of the corona. The spacecraft will be equipped with a wide field, super achromatic lens coronagraph equipped with two 100-slit, 4-channel spectropolarimeters optimized for measurement of the polarized CEL spectra from space. This instrument is tentatively named 'mxCSM'- the massively-multiplexed Coronal SpectroMagnetometer. A prototype mxCSM is currently under construction with funding from a 2017 National Science Foundation Major Research Instrument program grant. This space coronal space magnetometry mission will advance our knowledge of the corona and the physics of energetic coronal eruptions, and ultimately enable accurate space weather forecast. Title: Experimental testing of scattering polarization models Authors: Li, Wenxian; Casini, Roberto; Tomczyk, Steven; Landi Degl'Innocenti, Egidio; Marsell, Brandan Bibcode: 2018AAS...23212305L Altcode: We realized a laboratory experiment to study the polarization of the Na I doublet at 589.3 nm, in the presence of a magnetic field. The purpose of the experiment is to test the theory of scattering polarization for illumination conditions typical of astrophysical plasmas. This work was stimulated by solar observations of the Na I doublet that have proven particularly challenging to reproduce with current models of polarized line formation, even casting doubts on our very understanding of the physics of scattering polarization on the Sun. The experiment has confirmed the fundamental correctness of the current theory, and demonstrated that the "enigmatic'' polarization of those observations is exclusively of solar origin. Title: Eclipse Science from 50,000 Feet: New Coronal Results from NASA WB-57F High-Altitude Aircraft Observations of the 2017 Total Solar Eclipse Authors: Caspi, Amir; Tsang, Constantine; Seaton, Daniel B.; DeForest, Craig; Bryans, Paul; DeLuca, Edward; Tomczyk, Steven; Burkepile, Joan; Casey, Thomas Anthony; Collier, John; Darrow, Donald DD; Del Rosso, Dominic; Durda, Daniel D.; Gallagher, Peter; Gascar, Jasmine; Golub, Leon; Jacyna, Matthew; Johnson, David DJ; Judge, Philip G.; Klemm, Cary; Laurent, Glenn Thomas; Lewis, Johanna; Mallini, Charles; Parent, Thomas Duster; Propp, Timothy; Steffl, Andrew; Warner, Jeff; West, Matthew John; Wiseman, John; Yates, Mallory; Zhukov, Andrei Bibcode: 2018tess.conf31302C Altcode: Total solar eclipses present rare opportunities to study the complex solar corona, down to altitudes of just a few percent of a solar radius above the surface. Studying the corona is critical to gaining a better understanding of the dominant driver of space weather that affects human assets on Earth and elsewhere. For example, it is still poorly understood how the corona is heated to temperatures of 1-2 MK globally and up to 5-10 MK above active regions, while the underlying chromosphere is 100 times cooler. The stability of large-scale coronal structures and the extent of their reach to the middle and outer corona are also not well known, limited in large part by sensitivities and fields of view of existing observations.

Airborne observations during a total eclipse provide unique advantages. By flying in the stratosphere at altitudes of 50 kft or higher, they avoid all weather, the seeing quality is enormously improved, and additional wavelengths such as near-IR also become available due to significantly reduced water absorption. An airborne observatory can also follow the Moon's shadow, increasing the total observing time by 50% or more.

We present current results of solar coronal measurements from airborne observations of the 2017 Great American Total Solar Eclipse using two of NASA's WB-57 high-altitude research aircraft, each equipped with two 8.7-inch telescopes feeding high-sensitivity visible (green line and nearby continuum) and medium-wave IR (3-5 μm) cameras operating at high cadence (30 Hz) with ∼3 arcsec/pixel platescale and ±3 Rsun fields of view. The two aircraft flew along the eclipse path, separated by ∼110 km, to observe a total of ∼7.5 minutes of totality in both visible and MWIR. These observations enable groundbreaking studies of high-speed coherent motion - including possible Alfvén waves and nanojets - in the lower and middle corona that could shed light on coronal heating processes and the formation and stability of coronal structures. Our MWIR observations of a cool prominence and hot coronal active region plasma will be combined with spectra from the AIR-Spec instrument, flown concurrently on NCAR's HIAPER GV. We review the WB-57 eclipse mission and the current results of analysis on the visible and IR coronal measurements, along with an outlook for future analysis and missions. Title: Turbulence and Heating in the Flank and Wake Regions of a Coronal Mass Ejection Authors: Fan, Siteng; He, Jiansen; Yan, Limei; Tomczyk, Steven; Tian, Hui; Song, Hongqiang; Wang, Linghua; Zhang, Lei Bibcode: 2018SoPh..293....6F Altcode: As a coronal mass ejection (CME) passes, the flank and wake regions are typically strongly disturbed. Various instruments, including the Large Angle and Spectroscopic Coronagraph (LASCO), the Atmospheric Imaging Assembly (AIA), and the Coronal Multi-channel Polarimeter (CoMP), observed a CME close to the east limb on 26 October 2013. A hot (≈10 MK) rising blob was detected on the east limb, with an initial ejection flow speed of ≈330 kms−1. The magnetic structures on both sides and in the wake of the CME were strongly distorted, showing initiation of turbulent motions with Doppler-shift oscillations enhanced from ≈±3 kms−1 to ≈±15 kms−1 and effective thermal velocities from ≈30 kms−1 to ≈60 kms−1, according to the CoMP observations at the Fe XIII line. The CoMP Doppler-shift maps suggest that the turbulence behaved differently at various heights; it showed clear wave-like torsional oscillations at lower altitudes, which are interpreted as the antiphase oscillation of an alternating red/blue Doppler shift across the strands at the flank. The turbulence seems to appear differently in the channels of different temperatures. Its turnover time was ≈1000 seconds for the Fe 171 Å channel, while it was ≈500 seconds for the Fe 193 Å channel. Mainly horizontal swaying rotations were observed in the Fe 171 Å channel, while more vertical vortices were seen in the Fe 193 Å channel. The differential-emission-measure profiles in the flank and wake regions have two components that evolve differently: the cool component decreased over time, evidently indicating a drop-out of cool materials due to ejection, while the hot component increased dramatically, probably because of the heating process, which is suspected to be a result of magnetic reconnection and turbulence dissipation. These results suggest a new turbulence-heating scenario of the solar corona and solar wind. Title: Chasing the Great American 2017 Total Solar Eclipse: Coronal Results from NASA's WB-57F High-Altitude Research Aircraft Authors: Caspi, A.; Tsang, C.; DeForest, C. E.; Seaton, D. B.; Bryans, P.; Burkepile, J.; Casey, T. A.; Collier, J.; Darrow, D.; DeLuca, E.; Durda, D. D.; Gallagher, P.; Golub, L.; Judge, P. G.; Laurent, G. T.; Lewis, J.; Mallini, C.; Parent, T.; Propp, T.; Steffl, A.; Tomczyk, S.; Warner, J.; West, M. J.; Wiseman, J.; Zhukov, A. Bibcode: 2017AGUFMSH24A..05C Altcode: Total solar eclipses present rare opportunities to study the complex solar corona, down to altitudes of just a few percent of a solar radius above the surface, using ground-based and airborne observatories that would otherwise be dominated by the intense solar disk and high sky brightness. Studying the corona is critical to gaining a better understanding of physical processes that occur on other stars and astrophysical objects, as well as understanding the dominant driver of space weather that affects human assets at Earth and elsewhere. For example, it is still poorly understood how the corona is heated to temperatures of 1-2 MK globally and up to 5-10 MK above active regions, while the underlying chromosphere is 100 times cooler; numerous theories abound, but are difficult to constrain due to the limited sensitivities and cadences of prior measurements. The origins and stability of coronal fans, and the extent of their reach to the middle and outer corona, are also not well known, limited in large part by sensitivities and fields of view of existing observations. Airborne observations during the eclipse provide unique advantages; by flying in the stratosphere at altitudes of 50 kft or higher, they avoid all weather, the seeing quality is enormously improved, and additional wavelengths such as near- IR also become available due to significantly reduced water absorption. For an eclipse, an airborne observatory can also follow the shadow, increasing the total observing time by 50% or more. We present results of solar coronal measurements from airborne observations of the 2017 Great American Total Solar Eclipse using two of NASA's WB-57 high-altitude research aircraft, each equipped with two 8.7" telescopes feeding high-sensitivity visible (green-line) and medium-wave IR (3-5 μm) cameras operating at high cadence (30 Hz) with 3 arcsec/pixel platescale and ±3 R_sun fields of view. The aircraft flew along the eclipse path, separated by 110 km, to observe a summed 7.5 minutes of totality in both visible and NIR, enabling groundbreaking studies of high-speed wave motions and nanojets in the lower corona, the structure and extent of coronal fans, and constraints on a potential primordial dust ring around the Sun. We review the mission, and the results of analysis on the visible and IR coronal measurements. Title: Multi-wavelength observations of the solar atmosphere from the August 21, 2017 total solar eclipse Authors: Tomczyk, S.; Boll, A.; Bryans, P.; Burkepile, J.; Casini, R.; DeLuca, E.; Gibson, K. L.; Judge, P. G.; McIntosh, S. W.; Samra, J.; Sewell, S. D. Bibcode: 2017AGUFMSH24A..04T Altcode: We will conduct three experiments at the August 21, 2017 total solar eclipse that we call the Rosetta Stone experiments. First, we will obtain narrow-bandpass images at infrared wavelengths of the magnetically sensitive coronal emission lines of Fe IX 2855 nm, Mg VIII 3028 nm and Si IX 3935 nm with a FLIR thermal imager. Information on the brightness of these lines is important for identifying the optimal lines for coronal magnetometry. These images will also serve as context images for the airborne AirSpec IR coronal spectroscopy experiment (Samra et al). Second, we will obtain linear polarization images of the visible emission lines of Fe X 637 nm and Fe XI 789 nm as well as the continuum polarization near 735 nm. These will be obtained with a novel detector with an integral array of linear micro-polarizers oriented at four different angles that enable polarization images without the need for liquid crystals or rotating elements. These measurements will provide information on the orientation of magnetic fields in the corona and serve to demonstrate the new detector technology. Lastly, we will obtain high cadence spectra as the moon covers and uncovers the chromosphere immediately after 2nd contact and before third contact. This so-called flash spectrum will be used to obtain information about chromospheric structure at a spatial resolution higher than is possible by other means. In this talk, we will describe the instrumentation used in these experiments and present initial results obtained with them. This work is supported by a grant from NASA, through NSF base funding of HAO/NCAR and by generous loans of equipment from our corporate partners, FLIR, 4D Technologies and Avantes. Title: Polarization Observations of the Total Solar Eclipse of August 21, 2017 Authors: Burkepile, J.; Boll, A.; Casini, R.; de Toma, G.; Elmore, D. F.; Gibson, K. L.; Judge, P. G.; Mitchell, A. M.; Penn, M.; Sewell, S. D.; Tomczyk, S.; Yanamandra-Fisher, P. A. Bibcode: 2017AGUFMSH13B2477B Altcode: A total solar eclipse offers ideal sky conditions for viewing the solar corona. Light from the corona is composed of three components: the E-corona, made up of spectral emission lines produced by ionized elements in the corona; the K-corona, produced by photospheric light that is Thomson scattered by coronal electrons; and the F-corona, produced by sunlight scattered from dust particles in the near Sun environment and in interplanetary space. Polarized white light observations of the corona provide a way of isolating the K-corona to determine its structure, brightness, and density. This work focuses on broadband white light polarization observations of the corona during the upcoming solar eclipse from three different instruments. We compare coronal polarization brightness observations of the August 21, 2017 total solar eclipse from the NCAR/High Altitude Observatory (HAO) Rosetta Stone experiment using the 4-D Technology PolarCam camera with the two Citizen PACA_CATE17Pol telescopes that will acquire linear polarization observations of the eclipse and the NCAR/HAO K-Cor white light coronagraph observations from the Mauna Loa Solar Observatory in Hawaii. This comparison includes a discussion of the cross-calibration of the different instruments and reports the results of the coronal polarization brightness and electron density of the corona. These observations will be compared with results from previous coronal measurements taken at different phases of the solar cycle. In addition, we report on the performance of the three different polarimeters. The 4-D PolarCam uses a linear polarizer array, PACA_CATE17Pol uses a nematic liquid crystal retarder in a single beam configuration and K-Cor uses a pair of ferroelectric liquid crystal retarders in a dual-beam configuration. The use of the 4-D PolarCam camera in the Rosetta Stone experiment is to demonstrate the technology for acquiring high cadence polarization measurements. The Rosetta Stone experiment is funded through the NASA award NNH16ZDA001N-ISE. The Citizen Science approach to measuring the polarized solar corona during the eclipse is funded through NASA award NNX17AH76G. The NCAR Mauna Loa Solar Observatory is funded by the National Science Foundation. Title: Measuring Solar Coronal Magnetism during the Total Solar Eclipse of 2017 Authors: Gibson, K. L.; Tomczyk, S. Bibcode: 2017AGUFMSH13B2478G Altcode: The total solar eclipse on August 21, 2017 provided a notable opportunity to measure the solar corona at specific emission wavelengths to gain information about coronal magnetic fields. Solar magnetic fields are intimately related to the generation of space weather and its effects on the earth, and the infrared imaging and polarization information collected on coronal emission lines here will enhance the scientific value of several other ongoing experiments, as well as benefit the astrophysics and upper atmosphere communities. Coronal measurements were collected during the 2 minute and 24 second totality period from Casper Mountain, WY. Computer-controlled telescopes automatically inserted four different narrow band pass filters to capture images in the visible range on a 4D PolCam, and in the infrared range on the FLIR 8501c camera. Each band pass filter selects a specific wavelength range that corresponds to a known coronal emission line possessing magnetic sensitivity. The 4D PolCam incorporated a novel grid of linear polarizers precisely aligned with the micron scale pixels. This allowed for direct measurement of the degree of linear polarization in a very small instrument with no external moving parts as is typically required. The FLIR offers short exposure times to freeze motion and output accurate thermal measurements. This allowed a new observation of the sun's corona using thermo infrared technology. Title: ASPIRE - Airborne Spectro-Polarization InfraRed Experiment Authors: DeLuca, E.; Cheimets, P.; Golub, L.; Madsen, C. A.; Marquez, V.; Bryans, P.; Judge, P. G.; Lussier, L.; McIntosh, S. W.; Tomczyk, S. Bibcode: 2017AGUFMSH13B2480D Altcode: Direct measurements of coronal magnetic fields are critical for taking the next step in active region and solar wind modeling and for building the next generation of physics-based space-weather models. We are proposing a new airborne instrument to make these key observations. Building on the successful Airborne InfraRed Spectrograph (AIR-Spec) experiment for the 2017 eclipse, we will design and build a spectro-polarimeter to measure coronal magnetic field during the 2019 South Pacific eclipse. The new instrument will use the AIR-Spec optical bench and the proven pointing, tracking, and stabilization optics. A new cryogenic spectro-polarimeter will be built focusing on the strongest emission lines observed during the eclipse. The AIR-Spec IR camera, slit jaw camera and data acquisition system will all be reused. The poster will outline the optical design and the science goals for ASPIRE. Title: Eclipse Science Results from the Airborne Infrared Spectrometer (AIR-Spec) Authors: Samra, J.; Cheimets, P.; DeLuca, E.; Golub, L.; Judge, P. G.; Lussier, L.; Madsen, C. A.; Marquez, V.; Tomczyk, S.; Vira, A. Bibcode: 2017AGUFMSH24A..06S Altcode: We present the first science results from the commissioning flight of the Airborne Infrared Spectrometer (AIR-Spec), an innovative solar spectrometer that will observe the 2017 solar eclipse from the NSF/NCAR High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER). During the eclipse, AIR-Spec will image five magnetically sensitive coronal emission lines between 1.4 and 4 microns to determine whether they may be useful probes of coronal magnetism. The instrument will measure emission line intensity, FWHM, and Doppler shift from an altitude of over 14 km, above local weather and most of the absorbing water vapor. Instrumentation includes an image stabilization system, feed telescope, grating spectrometer, infrared camera, and visible slit-jaw imager. Results from the 2017 eclipse are presented in the context of the mission's science goals. AIR-Spec will identify line strengths as a function of position in the solar corona and search for the high frequency waves that are candidates for heating and acceleration of the solar wind. The instrument will also identify large scale flows in the corona, particularly in polar coronal holes. Three of the five lines are expected to be strong in coronal hole plasmas because they are excited in part by scattered photospheric light. Line profile analysis will probe the origins of the fast and slow solar wind. Finally, the AIR-Spec measurements will complement ground based eclipse observations to provide detailed plasma diagnostics throughout the corona. AIR-Spec will measure infrared emission of ions observed in the visible from the ground, giving insight into plasma heating and acceleration at radial distances inaccessible to existing or planned spectrometers. Title: First results from the NASA WB-57 airborne observations of the Great American 2017 Total Solar Eclipse Authors: Caspi, Amir; Tsang, Constantine; DeForest, Craig; Seaton, Daniel B.; Bryans, Paul; Tomczyk, Steven; Burkepile, Joan; Judge, Phil; DeLuca, Edward E.; Golub, Leon; Gallagher, Peter T.; Zhukov, Andrei; West, Matthew; Durda, Daniel D.; Steffl, Andrew J. Bibcode: 2017SPD....4810701C Altcode: Total solar eclipses present rare opportunities to study the complex solar corona, down to altitudes of just a few percent of a solar radius above the surface, using ground-based and airborne observatories that would otherwise be dominated by the intense solar disk and high sky brightness. Studying the corona is critical to gaining a better understanding of physical processes that occur on other stars and astrophysical objects, as well as understanding the dominant driver of space weather that affects human assets at Earth and elsewhere. For example, it is still poorly understood how the corona is heated to temperatures of 1-2 MK globally and up to 5-10 MK above active regions, while the underlying chromosphere is 100 times cooler; numerous theories abound, but are difficult to constrain due to the limited sensitivities and cadences of prior measurements. The origins and stability of coronal fans, and the extent of their reach to the middle and outer corona, are also not well known, limited in large part by sensitivities and fields of view of existing observations.Airborne observations during the eclipse provide unique advantages; by flying in the stratosphere at altitudes of 50 kft or higher, they avoid all weather, the seeing quality is enormously improved, and additional wavelengths such as near-IR also become available due to significantly reduced water absorption. For an eclipse, an airborne observatory can also follow the shadow, increasing the total observing time by 50% or more.We present the first results from airborne observations of the 2017 Great American Total Solar Eclipse using two of NASA's WB-57 research aircraft, each equipped with two 8.7" telescopes feeding high-sensitivity visible (green-line) and near-IR (3-5 µm) cameras operating at high cadence (30 Hz) with ~3 arcsec/pixel platescale and ±3 R_sun fields of view. The aircraft will fly along the eclipse path, separated by ~90 km, to observe a summed ~8 minutes of totality in both visible and NIR, enabling groundbreaking studies of high-speed wave motions and nanojets in the lower corona, the structure and extent of coronal fans, and constraints on a potential primordial dust ring around the Sun. Title: Magnetic Nulls and Super-radial Expansion in the Solar Corona Authors: Gibson, Sarah E.; Dalmasse, Kevin; Rachmeler, Laurel A.; De Rosa, Marc L.; Tomczyk, Steven; de Toma, Giuliana; Burkepile, Joan; Galloy, Michael Bibcode: 2017ApJ...840L..13G Altcode: 2017arXiv170407470G Magnetic fields in the Sun’s outer atmosphere—the corona—control both solar-wind acceleration and the dynamics of solar eruptions. We present the first clear observational evidence of coronal magnetic nulls in off-limb linearly polarized observations of pseudostreamers, taken by the Coronal Multichannel Polarimeter (CoMP) telescope. These nulls represent regions where magnetic reconnection is likely to act as a catalyst for solar activity. CoMP linear-polarization observations also provide an independent, coronal proxy for magnetic expansion into the solar wind, a quantity often used to parameterize and predict the solar wind speed at Earth. We introduce a new method for explicitly calculating expansion factors from CoMP coronal linear-polarization observations, which does not require photospheric extrapolations. We conclude that linearly polarized light is a powerful new diagnostic of critical coronal magnetic topologies and the expanding magnetic flux tubes that channel the solar wind. Title: 3D Global Coronal Density, Temperature, and Vector Magnetic Field Derived from Coronal Observation. Authors: Kramar, M.; Lin, H.; Airapetian, V.; Tomczyk, S. Bibcode: 2016AGUFMSH43A2558K Altcode: Solar coronal magnetic fields play a key role in the energetics and dynamics of coronal heating, solar flares, coronal mass ejections (CME), filament eruptions, and determine space weather processes. Therefore, one of the central problems of solar physics is to measure the magnetic fields in the solar corona.The main techniques that are currently used to deduce the global magnetic structure of the solar corona include potential field, nonlinear force-free field (NLFFF), and magnetohydrodynamic (MHD) models. These methods are based on boundary conditions of the solar photospheric magnetic field that are derived directly from photospheric magnetograms. All of these methods are essentially extrapolation methods based on inner boundary conditions taken at the photosphere. However, the magnetic field at the photosphere and lower chromosphere is far from potential or force-free, because of the dominance of the plasma pressure there.We will present 3D reconstruction of the global coronal electron density, temperature during periods of minimum and maximum of solar activity cycle and derived from coronal STEREO/COR1 and EUVI observations. We find that the magnetic field configuration during maximum of solar activity (CR 2131) has a tendency to become radially open at heliocentric distances below 2.5 Rsun while during the solar minimum (CR 2066) they tend to open at higher distances.Moreover, the obtained 3D density and temperature has been used as additional input for recently developed vector tomography method to reconstruct the coronal vector magnetic field based on polarimetric observation of magnetically sensitive Fe XIII ion emission by Coronal Magnetic Polarimeter (CoMP). We validated the vector tomography inverted coronal magnetic fields with those constructed by MHD simulation based on observed photospheric magnetic fields as well as with the STEREO/EUVI 195 image and with the global 3D coronal electron density structure obtained by tomography based on STEREO/COR1 data. Title: Exploring Coronal Dynamics: A Next Generation Solar Physics Mission white paper Authors: Morton, R. J.; Scullion, E.; Bloomfield, D. S.; McLaughlin, J. A.; Regnier, S.; McIntosh, S. W.; Tomczyk, S.; Young, P. Bibcode: 2016arXiv161106149M Altcode: Determining the mechanisms responsible for the heating of the coronal plasma and maintaining and accelerating the solar wind are long standing goals in solar physics. There is a clear need to constrain the energy, mass and momentum flux through the solar corona and advance our knowledge of the physical process contributing to these fluxes. Furthermore, the accurate forecasting of Space Weather conditions at the near-Earth environment and, more generally, the plasma conditions of the solar wind throughout the heliosphere, require detailed knowledge of these fluxes in the near-Sun corona. Here we present a short case for a space-based imaging-spectrometer coronagraph, which will have the ability to provide synoptic information on the coronal environment and provide strict constraints on the mass, energy, and momentum flux through the corona. The instrument would ideally achieve cadences of $\sim10$~s, spatial resolution of 1" and observe the corona out to 2~$R_{\sun}$. Such an instrument will enable significant progress in our understanding of MHD waves throughout complex plasmas, as well as potentially providing routine data products to aid Space Weather forecasting. Title: A Global View of Velocity Fluctuations in the Corona below 1.3 R with CoMP Authors: Morton, R. J.; Tomczyk, S.; Pinto, R. F. Bibcode: 2016ApJ...828...89M Altcode: 2016arXiv160801831M The Coronal Multi-channel Polarimeter (CoMP) has previously demonstrated the presence of Doppler velocity fluctuations in the solar corona. The observed fluctuations are thought to be transverse waves, I.e., highly incompressible motions whose restoring force is dominated by the magnetic tension, some of which demonstrate clear periodicity. We aim to exploit CoMP’s ability to provide high cadence observations of the off-limb corona to investigate the properties of velocity fluctuations in a range of coronal features, providing insight into how (whether) the properties of the waves are influenced by the varying magnetic topology in active regions, quiet Sun and open field regions. An analysis of Doppler velocity time-series of the solar corona from the 10747 Å Iron xiii line is performed, determining the velocity power spectrum and using it as a tool to probe wave behavior. Further, the average phase speed and density for each region are estimated and used to compute the spectra for energy density and energy flux. In addition, we assess the noise levels associated with the CoMP data, deriving analytic formulae for the uncertainty on Doppler velocity measurements and providing a comparison by estimating the noise from the data. It is found that the entire corona is replete with transverse wave behavior. The corresponding power spectra indicate that the observed velocity fluctuations are predominately generated by stochastic processes, with the spectral slope of the power varying between the different magnetic regions. Most strikingly, all power spectra reveal the presence of enhanced power occurring at ∼3 mHz, potentially implying that the excitation of coronal transverse waves by p-modes is a global phenomenon. Title: Coronal plasma diagnostics from ground-based observations Authors: Landi, E.; Habbal, S. R.; Tomczyk, S. Bibcode: 2016JGRA..121.8237L Altcode: In this paper we discuss the potential of ground-based visible observations of the solar corona to address the key open problems in the physics of the solar atmosphere and of solar activity. We first compare the diagnostic potential of visible observations with those of high-resolution spectrometers and narrowband imagers working in the EUV and X-ray wavelength ranges. We then review the main diagnostic techniques (and introduce a few new ones) that can be applied to line and continuum emission in the solar atmosphere, and the physical problems that they enable us to address. Finally, we briefly review the main features of ground-based coronographic instrumentation currently being developed and planned. Title: Scientific objectives and capabilities of the Coronal Solar Magnetism Observatory Authors: Tomczyk, S.; Landi, E.; Burkepile, J. T.; Casini, R.; DeLuca, E. E.; Fan, Y.; Gibson, S. E.; Lin, H.; McIntosh, S. W.; Solomon, S. C.; Toma, G.; Wijn, A. G.; Zhang, J. Bibcode: 2016JGRA..121.7470T Altcode: Magnetic influences increase in importance in the solar atmosphere from the photosphere out into the corona, yet our ability to routinely measure magnetic fields in the outer solar atmosphere is lacking. We describe the scientific objectives and capabilities of the COronal Solar Magnetism Observatory (COSMO), a proposed synoptic facility designed to measure magnetic fields and plasma properties in the large-scale solar atmosphere. COSMO comprises a suite of three instruments chosen to enable the study of the solar atmosphere as a coupled system: (1) a coronagraph with a 1.5 m aperture to measure the magnetic field, temperature, density, and dynamics of the corona; (2) an instrument for diagnostics of chromospheric and prominence magnetic fields and plasma properties; and (3) a white light K-coronagraph to measure the density structure and dynamics of the corona and coronal mass ejections. COSMO will provide a unique combination of magnetic field, density, temperature, and velocity observations in the corona and chromosphere that have the potential to transform our understanding of fundamental physical processes in the solar atmosphere and their role in the origins of solar variability and space weather. Title: Systems engineering overview and concept of operations of the COronal Solar Magnetism Observatory (COSMO) Authors: Oakley, P. H. H.; Tomczyk, S.; Sewell, S.; Gallagher, D.; Larson, B. Bibcode: 2016SPIE.9911E..2IO Altcode: The COronal Solar Magnetism Observatory (COSMO) is a proposed facility with unique capabilities for magnetic field measurements in the solar atmosphere and corona to increase our understanding of solar physics and space weather. The observatory underwent a preliminary design review (PDR) in 2015. This paper summarizes the systems engineering plan for this facility as well as a preliminary overview of the concept of operations. In particular we detail the flow of science requirements to engineering requirements, and discuss an overview of requirements management, documentation management, interface control and overall verification and compliance processes. Operationally, we discuss the categories of operational modes, as well as an overview of a daily operational cycle. Title: Development of a tunable filter for coronal polarimetry Authors: Tomczyk, S.; Mathew, S. K.; Gallagher, D. Bibcode: 2016JGRA..121.6184T Altcode: Measuring magnetic fields in the solar corona is crucial to understanding and predicting the Sun's generation of space weather that affects communications, GPS systems, space flight, and power transmission. The Coronal Solar Magnetism Observatory Large Coronagraph (COSMO LC) is a proposed 1.5 m aperture coronagraph designed to synoptically observe magnetic fields and plasma properties in the large-scale corona to improve our understanding of solar processes that cause space weather. The LC will observe coronal emission lines over the wavelength range from 500 to 1100 nm with a field of view of 1° and a spatial resolution of 2 arcsec. A spectral resolution greater than 8000 over the wavelength range is needed to resolve the polarization signatures of magnetic fields in the emission line profiles. The aperture and field of view of the LC set an étendue requirement of 1.39 m2 deg2 for the postfocus instrumentation. We find that a tunable wide-field birefringent filter using Lithium Niobate crystals can meet the étendue and spectral resolution requirements for the LC spectrometer. We have tested a number of commercially available crystals and verify that crystals of the required size and birefringence uniformity are available. We also evaluate electro-optical tuning of a Lithium Niobate birefringent filter by the application of high voltage. This tunable filter represents a key enabling technology for the COSMO LC. Title: The COSMO coronagraph optical design and stray light analysis Authors: Gallagher, Dennis; Wu, Zhen; Larson, Brandon; Nelson, Peter G.; Oakley, Phil; Sewell, Scott; Tomczyk, Steven Bibcode: 2016SPIE.9906E..54G Altcode: The Coronal Solar Magnetism Observatory Large Coronagraph (COSMO-LC) is a 1.5 meter Lyot coronagraph dedicated to measuring magnetic fields and plasma properties in the solar corona. The COSMO-LC will be able to observe coronal emissions lines from 530-1100 nm using a filtergraph instrument. COSMO-LC will have a 1 degree field of view to observe the full solar corona out to 1 solar radius beyond the limb of the sun. This presented challenges due to the large Etendue of the system. The COSMO-LC spatial resolution is 2 arc-seconds per pixel (4k X 4k). The most critical part of the coronagraph is the objective lens that is exposed to direct sunlight that is five orders of magnitude brighter than the corona. Therefore, it is key to the operation of a coronagraph that the objective lens (O1) scatter as little light as possible, on order a few parts per million. The selection of the material and the polish applied to the O1 are critical in reducing scattered light. In this paper we discuss the design of the COSMO-LC and the detailed design of the O1 and other key parts of the COSMO-LC that keep stray light to a minimum. The result is an instrument with stray light below 5 millionths the brightness of the sun 50 arc-seconds from the sun. The COSMO-LC has just had a Preliminary Design Review (PDR) and the PDR design is presented. Title: What’s New at the Mauna Loa Solar Observatory Authors: Burkepile, Joan; de Toma, Giuliana; Galloy, Michael; Kolinski, Don; Berkey, Ben; Stueben, Allen; Tomczyk, Steven; De Wijn, Alfred; Casini, Roberto; Card, Greg; Larson, Brandon; Stanger, Andrew; Oakley, Phil; Gallagher, Dennis; Waters, Lisa; Rose, Greg; Sewell, Scott Bibcode: 2016SPD....47.0801B Altcode: The Mauna Loa Solar Observatory (MLSO) is located at 3440 meters on the island of Hawaii. The site provides the dark, clear skies required for observing the solar corona. The National Center for Atmosphere Research (NCAR) High Altitude Observatory (HAO) operates two coronagraphs at the site: the Coronal Multi-Channel Polarimeter (CoMP) and the COSMO K-Coronagraph (K-Cor). CoMP is designed to study coronal magnetic fields by observing full Stokes polarimetry of two forbidden emission lines of FeXIII at 1074.7 and 1079.8 nm. CoMP also observes active and erupting prominences over the solar limb in neutral Helium emission at 1083.nm. The K-Cor is designed to study the onset and early evolution of coronal mass ejections (CMEs). It is the only white light coronagraph to routinely view the low corona down to 1.05 solar radii in order to capture the formation of CMEs. Information is provided on new Helium data products of active and erupting prominences observed by the CoMP instrument as well as results from the K-Cor observations of CMEs. Information on current and upcoming upgrades to the MLSO facility, instrument hardware, and calibrations are reported along with an accounting of new data products, tools and services from the MLSO website. Title: The CoMP-S Instrument at the Lomnický Peak Observatory: Status Report Authors: Kučera, A.; Ambróz, J.; Gömöry, P.; Habaj, P.; Kavka, J.; Kozák, M.; Schwartz, P.; Rybák, J.; Tomczyk, S.; Sewell, S.; Aumiller, P.; Summers, R.; Watt, A. Bibcode: 2016ASPC..504..321K Altcode: The Coronal Multi-channel Polarimeter for Slovakia (CoMP-S) has been installed at the high-altitude Lomnicky Peak Observatory of the Astronomical Institute of SAS (2633 m a.s.l.) in 2011. The instrument was designed and manufactured by HAO/NCAR (Boulder, USA) with a tunable Lyot filter and polarimeter for visible and near IR spectral regions. This instrument is proposed for coronagraphic observations of magnetic and velocity fields in the solar corona and in prominences. A fundamental upgrade of this instrument has been prepared with pair of cameras sensitive in the near IR spectral region in a new camera module. This upgrade is being incorporated to the instrument in course of the year 2014. In this contribution the technical parameters of the final configuration of the CoMP-S instrument containing four cameras, covering both visible and near IR spectral regions, are described. We also present a potential of the CoMP-S instrument for coronagraphic spectro-polarimetric observations of the solar corona and prominences with a capability for sequential measurements of the spectral profiles of all prominent emission lines in spectral region from 500 to 1100 nm. Title: Direct Observation of Solar Coronal Magnetic Fields by Vector Tomography of the Coronal Emission Line Polarizations Authors: Kramar, M.; Lin, H.; Tomczyk, S. Bibcode: 2016ApJ...819L..36K Altcode: 2015arXiv150207200K We present the first direct “observation” of the global-scale, 3D coronal magnetic fields of Carrington Rotation (CR) Cycle 2112 using vector tomographic inversion techniques. The vector tomographic inversion uses measurements of the Fe xiii 10747 Å Hanle effect polarization signals by the Coronal Multichannel Polarimeter (CoMP) and 3D coronal density and temperature derived from scalar tomographic inversion of Solar Terrestrial Relations Observatory (STEREO)/Extreme Ultraviolet Imager (EUVI) coronal emission lines (CELs) intensity images as inputs to derive a coronal magnetic field model that best reproduces the observed polarization signals. While independent verifications of the vector tomography results cannot be performed, we compared the tomography inverted coronal magnetic fields with those constructed by magnetohydrodynamic (MHD) simulations based on observed photospheric magnetic fields of CR 2112 and 2113. We found that the MHD model for CR 2112 is qualitatively consistent with the tomography inverted result for most of the reconstruction domain except for several regions. Particularly, for one of the most noticeable regions, we found that the MHD simulation for CR 2113 predicted a model that more closely resembles the vector tomography inverted magnetic fields. In another case, our tomographic reconstruction predicted an open magnetic field at a region where a coronal hole can be seen directly from a STEREO-B/EUVI image. We discuss the utilities and limitations of the tomographic inversion technique, and present ideas for future developments. Title: Waves and Magnetism in the Solar Atmosphere (WAMIS) Authors: Ko, Yuan-Kuen; Moses, John; Laming, John; Strachan, Leonard; Tun Beltran, Samuel; Tomczyk, Steven; Gibson, Sarah; Auchere, Frederic; Casini, Roberto; Fineschi, Silvano; Knoelker, Michael; Korendyke, Clarence; McIntosh, Scott; Romoli, Marco; Rybak, Jan; Socker, Dennis; Vourlidas, Angelos; Wu, Qian Bibcode: 2016FrASS...3....1K Altcode: Comprehensive measurements of magnetic fields in the solar corona have a long history as an important scientific goal. Besides being crucial to understanding coronal structures and the Sun’s generation of space weather, direct measurements of their strength and direction are also crucial steps in understanding observed wave motions. In this regard, the remote sensing instrumentation used to make coronal magnetic field measurements is well suited to measuring the Doppler signature of waves in the solar structures. In this paper, we describe the design and scientific values of the Waves and Magnetism in the Solar Atmosphere (WAMIS) investigation. WAMIS, taking advantage of greatly improved infrared filters and detectors, forward models, advanced diagnostic tools and inversion codes, is a long-duration high-altitude balloon payload designed to obtain a breakthrough in the measurement of coronal magnetic fields and in advancing the understanding of the interaction of these fields with space plasmas. It consists of a 20 cm aperture coronagraph with a visible-IR spectro-polarimeter focal plane assembly. The balloon altitude would provide minimum sky background and atmospheric scattering at the wavelengths in which these observations are made. It would also enable continuous measurements of the strength and direction of coronal magnetic fields without interruptions from the day-night cycle and weather. These measurements will be made over a large field-of-view allowing one to distinguish the magnetic signatures of different coronal structures, and at the spatial and temporal resolutions required to address outstanding problems in coronal physics. Additionally, WAMIS could obtain near simultaneous observations of the electron scattered K-corona for context and to obtain the electron density. These comprehensive observations are not provided by any current single ground-based or space observatory. The fundamental advancements achieved by the near-space observations of WAMIS on coronal field would point the way for future ground based and orbital instrumentation. Title: The Coronal Solar Magnetism Observatory Authors: Tomczyk, S.; Landi, E.; Zhang, J.; Lin, H.; DeLuca, E. E. Bibcode: 2015AGUFMSH43B2460T Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the processes responsible for coronal heating, coronal dynamics and the generation of space weather that affects communications, GPS systems, space flight, and power transmission. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment, and to understand the formation of coronal mass ejections (CME) and their relation to other forms of solar activity. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) with partners at the University of Michigan, the University of Hawaii and George Mason University in support of the solar and heliospheric community. It will replace the current NCAR Mauna Loa Solar Observatory (http://mlso.hao.ucar.edu). COSMO will enhance the value of existing and new observatories on the ground and in space by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. The design and current status of the COSMO will be reviewed. Title: Coronal plasma diagnostics from eclipse observations Authors: Landi, E.; Habbal, S. R.; Tomczyk, S. Bibcode: 2015AGUFMSH51C2456L Altcode: In this talk we will discuss the diagnostic potential of observationsof visible spectral lines formed in the extended solar corona that canbe obtained during eclipses. We will discuss the possible diagnosticapplications of visible eclipse observations to measure the physicalparameters of the extended corona, to understand solar wind origin andacceleration, and to determine the evolution of Coronal Mass Ejectionsduring onset.We will first review the mechanisms of formation of spectral lineintensities, we will then illustrate their diagnostic applications,and show some results from recent eclipse observations. We will alsoreview the spectral lines that are most likely to be observed inthe extended solar corona during the upcoming 2017 eclipse in thecontinental United States. Title: Waves and Magnetism in the Solar Atmosphere (WAMIS) Authors: Strachan, L.; Ko, Y. -K.; Moses, J. D.; Laming, J. M.; Auchere, F.; Casini, R.; Fineschi, S.; Gibson, S.; Knoelker, M.; Korendyke, C.; Mcintosh, S.; Romoli, M.; Rybak, J.; Socker, D.; Tomczyk, S.; Vourlidas, A.; Wu, Q. Bibcode: 2015IAUS..305..121S Altcode: Magnetic fields in the solar atmosphere provide the energy for most varieties of solar activity, including high-energy electromagnetic radiation, solar energetic particles, flares, and coronal mass ejections, as well as powering the solar wind. Despite the fundamental role of magnetic fields in solar and heliospheric physics, there exist only very limited measurements of the field above the base of the corona. What is needed are direct measurements of not only the strength and orientation of the magnetic field but also the signatures of wave motions in order to better understand coronal structure, solar activity, and the role of MHD waves in heating and accelerating the solar wind. Fortunately, the remote sensing instrumentation used to make magnetic field measurements is also well suited to measure the Doppler signature of waves in the solar structures. We present here a mission concept for the Waves And Magnetism In the Solar Atmosphere (WAMIS) experiment which is proposed for a NASA long-duration balloon flight. Title: 3D Observation of the Global Coronal Magnetic Field by Vector Tomography using the Coronal Emission Linear Polarization Data. Authors: Kramar, Maxim; Lin, Haosheng; Tomczyk, Steven Bibcode: 2015IAUGA..2257404K Altcode: Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal phenomena at all scales. However, due to the low density and opacity of the solar atmosphere, the coronal emission measurements are result of a line-of-sight (LOS) integration through a nonuniform temperature, density and magnetic field distribution. Therefore, except in a few special cases, a direct inference of the 3D coronal magnetic field structure from polarization data is in general not possible. Tomography methods allow to resolve the LOS problem.We will present the global-scale, 3D coronal vector magnetic fields obtained by a vector tomographic inversion technique.The Vector tomographic inversion uses measurements of the Fe XIII 10747 A Hanle effect linear polarization signals by the Coronal Multichannel Polarimeter (CoMP) as inputs to derive a coronal magnetic field model that best reproduces the observed polarization signals. The 3D electron density and temperature, needed as additional input, have been reconstructed by scalar field tomography method based on STEREO/EUVI data. We will present the 3D coronal vector magnetic field, electron density and temperature resulted from these inversions.While independent verifications of the vector tomography results cannot be performed, we compared the tomography inverted coronal magnetic fields with those constructed by MagnetoHydroDynamic (MHD) simulation based on observed photospheric magnetic fields and with 3D coronal density structures obtained by scalar field tomography based on coronal observations. We will discuss the utilities and limitations of the inversion technique, and present ideas for future developments. Title: Dual instrument for Flare and CME onset observations - Double solar Coronagraph with Solar Chromospheric Detector and Coronal Multi-channel Polarimeter at Lomnicky stit Observatory Authors: Kucera, Ales; Tomczyk, Steven; Rybak, Jan; Sewell, Scott; Gomory, Peter; Schwartz, Pavol; Ambroz, Jaroslav; Kozak, Matus Bibcode: 2015IAUGA..2246687K Altcode: We report on unique dual instrument developed for simultaneous measurements of velocity and magnetic fields in the solar chromosphere and corona. We describe the technical parameters and capability of the Coronal Multi-channel Polarimeter (CoMP-S) and Solar Chromospheric detector (SCD) mounted at the Double solar coronagraph at Lomnicky Stit Observatory and working simultaneously with strictly parallel pointing of both coronagraphs. The CoMP-S is 2D spectropolarimeter designed for observations of VIS and near-IR emission lines of prominences and corona with operating spectral range: 500 - 1100 nm, sequential measurement of several VIS and near-IR lines. Its field of view is 14 arcmin x 11 arcmin. It consists of 4-stage calcite Lyot filter followed by the ferro-liquid crystal polarizer and four cameras (2 visible, 2 infrared). The capability is to deliver 2D full Stokes I, Q, U, V, using registration with 2 IR cameras (line + background) and 2 VIS cameras (line + background) SCD is a single beam instrument to observe bright chromosphere. It is a combination of tunable filter and polarimeter. Spectral resolution of the SCD ranges from 0.046 nm for observations of the HeI 1083 nm line up to to 25 pm is for observation of the HeI 587.6 nm line. The birefringent filter of the SCD has high spectral resolution, as well as spatial resolution (1.7 arcseconds) and temporal resolution (10 seconds) First results are also reported and discussed. Title: Investigating Alfvénic wave propagation in coronal open-field regions Authors: Morton, R. J.; Tomczyk, S.; Pinto, R. Bibcode: 2015NatCo...6.7813M Altcode: 2015NatCo...6E7813M The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén waves. The existence of Alfvén waves far from the Sun has been known since the 1970s, and recently the presence of ubiquitous Alfvénic waves throughout the solar atmosphere has been confirmed. However, the presence of atmospheric Alfvénic waves does not, alone, provide sufficient support for wave-based models; the existence of counter-propagating Alfvénic waves is crucial for the development of turbulence. Here, we demonstrate that counter-propagating Alfvénic waves exist in open coronal magnetic fields and reveal key observational insights into the details of their generation, reflection in the upper atmosphere and outward propagation into the solar wind. The results enhance our knowledge of Alfvénic wave propagation in the solar atmosphere, providing support and constraints for some of the recent Alfvén wave turbulence models. Title: The CoMP Instrument and Data Processing Authors: Plowman, Joseph E.; de Toma, Giuliana; Tomczyk, Steven Bibcode: 2015TESS....130901P Altcode: We present an overview of the Coronal Multichannel Polarimeter (CoMP) coronagraph instrument, which observes infrared lines sensitive to the magnetic field in the solar corona. The overview covers the general properties of the instrument, its sensitivity to solar phenomena of interest, and sources of error and uncertainty in its data. We also show some updated results and processing of the data, which include improved coalignment and updated calibration (flat-fielding, dark subtraction, and polarization cross-talk). The ultimate goal of this processing is more clearly resolving the linear polarization signal (especially of the weaker 10798 Angstrom line) in the data and eventually resolving the Stokes V signal as well. Title: 3D Coronal Magnetic Field Reconstruction Based on Infrared Polarimetric Observations Authors: Kramar, M.; Lin, H.; Tomczyk, S. Bibcode: 2014AGUFMSH13A4069K Altcode: Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal phenomena at all scales. A significant progress has been recently achieved here with deployment of the Coronal Multichannel Polarimeter (CoMP) of the High Altitude Observatory (HAO). The instrument provides polarization measurements of Fe xiii 10747 A forbidden line emission. The observed polarization are the result of a line-of-sight (LOS) integration through a nonuniform temperature, density and magnetic field distribution. In order resolve the LOS problem and utilize this type of data, the vector tomography method has been developed for 3D reconstruction of the coronal magnetic field. The 3D electron density and temperature, needed as additional input, have been reconstructed by tomography method based on STEREO/EUVI data. We will present the 3D coronal magnetic field and associated 3D curl B, density, and temperature resulted from these inversions. Title: The Coronal Solar Magnetism Observatory (COSMO) Authors: Tomczyk, S.; Landi, E.; Lin, H.; Zhang, J. Bibcode: 2014AGUFMSH53B4212T Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required in our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. However, routine observations of the strength and orientation of coronal and chromospheric magnetic fields are not currently available. COSMO is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment. We will present an overview of the COSMO and show recent progress in development of the COSMO observatory. Title: Waves and Magnetism in the Solar Atmosphere (WAMIS) Authors: Ko, Y. K.; Auchere, F.; Casini, R.; Fineschi, S.; Gibson, S. E.; Knoelker, M.; Korendyke, C.; Laming, J. M.; Mcintosh, S. W.; Moses, J. D.; Romoli, M.; Rybak, J.; Socker, D. G.; Strachan, L.; Tomczyk, S.; Vourlidas, A.; Wu, Q. Bibcode: 2014AGUFMSH53B4221K Altcode: Magnetic fields in the solar atmosphere provide the energy for most varieties of solar activity, including high-energy electromagnetic radiation, solar energetic particles, flares, and coronal mass ejections, as well as powering the solar wind. Despite the fundamental role of magnetic fields in solar and heliospheric physics, there exists only very limited measurements of the field above the base of the corona. What is needed are direct measurements of not only the strength and orientation of the magnetic field but also the signatures of wave motions in order to better understand coronal structure, solar activity and the role of MHD waves in heating and accelerating the solar wind. Fortunately, the remote sensing instrumentation used to make magnetic field measurements is also well suited for measuring the Doppler signature of waves in the solar structures. With this in mind, we are proposing the WAMIS (Waves and Magnetism in the Solar Atmosphere) investigation. WAMIS will take advantage of greatly improved infrared (IR) detectors, forward models, advanced diagnostic tools and inversion codes to obtain a breakthrough in the measurement of coronal magnetic fields and in the understanding of the interaction of these fields with space plasmas. This will be achieved with a high altitude balloon borne payload consisting of a coronagraph with an IR spectro-polarimeter focal plane assembly. The balloon platform provides minimum atmospheric absorption and scattering at the IR wavelengths in which these observations are made. Additionally, a NASA long duration balloon flight mission from the Antarctic can achieve continuous observations over most of a solar rotation, covering all of the key time scales for the evolution of coronal magnetic fields. With these improvements in key technologies along with experience gained from current ground-based instrumentation, WAMIS will provide a low-cost mission with a high technology readiness leve. Title: Turbulence and Heating in the Side and Wake Regions of Coronal Mass Ejection in the Low Corona Authors: Fan, S.; He, J.; Yan, L.; Zhang, L.; Tomczyk, S. Bibcode: 2014AGUFMSH12A..06F Altcode: Ahead of CMEs usually exist the shocked sheaths, in which the background solar corona / solar wind is heated due to the compression of the driving CME. The other regions around the CME, e.g., the side and wake, which may also be influenced by the CME, are the objects of this work. Various instruments including LASCO, AIA, and CoMP observed a CME close to the east limb on October 26th, 2013. The CME core is very hot (~10 MK) (appearing only in the 131 channel of AIA), and ejects away at a high speed (~330 km/s). Magnetic structures (low-lying loops and large loop legs) on both sides and in the wake of the CME are strongly disturbed, showing turbulent signatures with enhanced Doppler-shift oscillations (~±15km/s) and effective thermal velocities (~60 km/s) from the CoMP observations in the Fe XIII line. As recognized from the CoMP Doppler-shift maps, the turbulent vortices behave differently at various heights, illustrating torsional oscillations back and forth around the leg axis at lower altitude and continuous rotation with the same handedness at higher altitude. This difference may be due to the lower part being more likely to be line-tied with the motionless footpoint than the upper part. The turbulence of loop legs is also revealed in the AIA animations in the Fe 171 Å and Fe 193 Å channels with some differences between each other. The turbulence in Fe 171 Å seems to be weaker than that in Fe 193 Å, with the former behaving more wave-like and the latter involving more whirling vortices. The difference in turbulence level might come from the difference in turnover time of the vortices: ~1000s for Fe 171 Å and ~500s for Fe 193 Å. Moreover, in the wake of the CME, the eddies turning over up and down as well as the eddies rotating horizontally are also presented in the Fe 193 Å. The leg-like straps in Fe 171 Å seem to be braided by the turbulent vortices, and disappear afterwards probably due to heating by coherent current sheet formed between braided straps. Meanwhile, low-lying loops are oscillating back and forth during its reaction to the fast compressive waves as driven by the CME. The subsequent brightening of the low-lying loops implies a heating due to the dissipation of compressive waves. This work suggests that the effects at the side and wake of the CME cannot be ignored when considering the heating of the solar corona and solar wind. Title: A Progress Update for the COronal Solar Magnetism Observatory for Coronal and Chromospheric Polarimetry Authors: de Wijn, A. G.; Tomczyk, S.; Burkepile, J. Bibcode: 2014ASPC..489..323D Altcode: We present a progress update for the COronal Solar Magnetism Observatory (COSMO), consisting of a suite of three instruments: a large-aperture coronagraph for coronal magnetometry, a full-disk imaging spectro-polarimeter for magnetometry and plasma diagnostics of the chromosphere and prominences, and a white-light coronagraph to observe the K-corona. COSMO will provide unique observations of the global coronal magnetic fields and its environment to enhance the value of data collected by other observatories on the ground and in space. We provide an overview of COSMO, and discuss each instrument in some detail. Title: 3D Coronal Magnetic Field Reconstruction based on infrared polarimetric observations Authors: Kramar, Maxim; Lin, Haosheng; Tomczyk, Steven Bibcode: 2014shin.confE.102K Altcode: Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal phenomena at all scales. A significant progress has been recently achieved here with deployment of the Coronal Multichannel Polarimeter (CoMP) of the High Altitude Observatory (HAO). The instrument provides polarization measurements of Fe xiii 10747 A forbidden line emission. The observed polarization are the result of a line-of-sight (LOS) integration through a nonuniform temperature, density and magnetic field distribution. In order resolve the LOS problem and utilize this type of data, the vector tomography method has been developed for 3D reconstruction of the coronal magnetic field. The 3D electron density and temperature, needed as additional input, have been reconstructed by tomography method based on STEREO/EUVI data. We will present the 3D coronal density, temperature and magnetic field resulted from these inversions. Title: Single-point Inversion of the Coronal Magnetic Field Authors: Plowman, Joseph; Casini, Roberto; Judge, Philip G.; Tomczyk, Steven Bibcode: 2014AAS...22432324P Altcode: The Fe XIII 10747 and 10798 Å lines observed in the solar corona are sensitive to the coronal magnetic field in such a way that, in principle, the full vector field at a point on the line of sight can be inferred from their combined polarization signals. This paper presents analytical inversion formulae for the field parameters and analyzes the uncertainty of magnetic field measurements made from such observations, assuming emission dominated by a single region along the line-of-sight. We consider the case of the current CoMP instrument as well as the future COSMO and ATST instruments. Uncertainties are estimated with a direct analytic inverse and with an MCMC algorithm. We find that (in effect) two components of the vector field can be recovered with CoMP, and well-recovered with COSMO or ATST, but that the third component can only be recovered when the solar magnetic field is strong and optimally oriented. Title: The Chromosphere and Prominence Magnetometer Authors: de Wijn, Alfred G.; McIntosh, Scott W.; Tomczyk, Steven Bibcode: 2014shin.confE..76D Altcode: The Chromosphere and Prominence Magnetometer (ChroMag) is a synoptic instrument with the goal of quantifying the intertwined dynamics and magnetism of the solar chromosphere and in prominences through imaging spectro-polarimetry of the full solar disk in a synoptic fashion. The picture of chromospheric magnetism and dynamics is rapidly developing, and a pressing need exists for breakthrough observations of chromospheric vector magnetic field measurements at the true lower boundary of the heliospheric system. ChroMag will provide measurements that will enable scientists to study and better understand the energetics of the solar atmosphere, how prominences are formed, how energy is stored in the magnetic field structure of the atmosphere and how it is released during space weather events like flares and coronal mass ejections. An essential part of the ChroMag program is a commitment to develop and provide community access to the `inversion' tools necessary to interpret the measurements and derive the magneto-hydrodynamic parameters of the plasma. Measurements of an instrument like ChroMag provide critical physical context for the Solar Dynamics Observatory (SDO) and Interface Region Imaging Spectrograph (IRIS) as well as ground-based observatories such as the future Daniel K. Inouye Solar Telescope (DKIST).

A prototype is currently deployed in Boulder, CO, USA. We will present an overview of instrument capabilities and a progress update on the ChroMag development. Title: Coronal Multi-channel Polarimeter at the Lomnicky Peak Observatory Authors: Schwartz, P.; Ambroz, J.; Gömöry, P.; Kozák, M.; Kučera, A.; Rybák, J.; Tomczyk, S.; Sewell, S.; Aumiller, P.; Summers, R.; Sutherland, L.; Watt, A. Bibcode: 2014IAUS..300..521S Altcode: Coronal Multi-channel Polarimeter (CoMP-S), developed by HAO/NCAR, has been introduced to regular operation at the Lomnicky Peak Observatory (High Tatras in northern Slovakia, 2633 m a.s.l.) of the Astronomical Institute of Slovak Academy of Sciences. We present here the technical parameters of the current version of the instrument and its potential for observations of prominences in the visual and near-IR spectral regions. The first results derived from observations of prominences in the Hα emission line taken during a coordinated observing campaign of several instruments in October 2012 are shown here. Title: Coronal Magnetometry in the Future Authors: Li, Hui; Tomczyk, Steven Bibcode: 2014cosp...40E1809L Altcode: Coronal magnetic field plays a crucial role in solar activity. However, due to the high temperature, low density and weak magnetic field properties of the corona, it is hard to directly measure coronal magnetic field, especially for the vector magnetic field. In this presentation, I will briefly review the past endeavor to measure the coronal magnetic field and present current methodology. I will introduce in more detail about the proposed Coronal Magnetism Telescopes of China (COMTEC) and the Coronal Solar Magnetism Observatory (COSMO) in the United States of America. Both of them are dedicated to measure the vector magnetic field in the corona as well as chromospheric magnetic field. They, once established, will certainly contribute much to the comprehensive understanding of important questions in solar physics, such as coronal and chromospheric heating, solar wind acceleration, global and long-time variation of coronal magnetic field, etc. Title: Preface Authors: Tomczyk, Steven; Zhang, Jie; Bastian, Timothy; Leibacher, John W. Bibcode: 2013SoPh..288..463T Altcode: No abstract at ADS Title: Observations of Coronal Mass Ejections with the Coronal Multichannel Polarimeter Authors: Tian, H.; Tomczyk, S.; McIntosh, S. W.; Bethge, C.; de Toma, G.; Gibson, S. Bibcode: 2013SoPh..288..637T Altcode: 2013arXiv1303.4647T The Coronal Multichannel Polarimeter (CoMP) measures not only the polarization of coronal emission, but also the full radiance profiles of coronal emission lines. For the first time, CoMP observations provide high-cadence image sequences of the coronal line intensity, Doppler shift, and line width simultaneously over a large field of view. By studying the Doppler shift and line width we may explore more of the physical processes of the initiation and propagation of coronal mass ejections (CMEs). Here we identify a list of CMEs observed by CoMP and present the first results of these observations. Our preliminary analysis shows that CMEs are usually associated with greatly increased Doppler shift and enhanced line width. These new observations provide not only valuable information to constrain CME models and probe various processes during the initial propagation of CMEs in the low corona, but also offer a possible cost-effective and low-risk means of space-weather monitoring. Title: Design and measurement of the Stokes polarimeter for the COSMO K-coronagraph Authors: Hou, Junfeng; de Wijn, Alfred G.; Tomczyk, Steven Bibcode: 2013ApJ...774...85H Altcode: We present the Stokes polarimeter for the new Coronal Solar Magnetism Observatory K-coronagraph. The polarimeter can be used in two modes. In observation mode, it is sensitive to linear polarization only and operates as a "Stokes definition" polarimeter. In the ideal case, such a modulator isolates a particular Stokes parameter in each modulation state. For calibrations, the polarimeter can diagnose the full Stokes vector. We present here the design process of the polarimeter, analyze its tolerances with a Monte Carlo method, develop a way to align the individual elements, and measure and evaluate its performance in both modes. Title: The Coronal Solar Magnetism Observatory Authors: Tomczyk, Steven; Sewell, Scott; Gallagher, Dennis; Oakley, Phil; Summers, Rich; Burkepile, Joan; Kolinski, Don; Sutherland, Lee; Zhang, Haiying; Wu, Zhen; Nelson, Pete Bibcode: 2013shin.confE..54T Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the processes responsible for coronal heating, coronal dynamics and the generation of space weather that affects communications, GPS systems, space flight, and power transmission. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment, and to understand the formation of coronal mass ejections (CME) and their relation to other forms of solar activity. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) in support of the solar and heliospheric community. It will replace the current NCAR Mauna Loa Solar Observatory (http://mlso.hao.ucar.edu). COSMO will enhance the value of existing and new observatories on the ground (SOLIS, BBO NST, Gregor, ATST, EST, Chinese Giant Solar Telescope, NLST, FASR) and in space (SOHO, GOES, Hinode, STEREO, SDO, IRIS, Solar-C, Solar Probe+, Solar Orbiter) by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. Title: Coronal Magnetic Field Reconstruction based on HAO/CoMP observations. Authors: Kramar, Maxim; Lin, H.; Tomczyk, S.; Davila, J. Bibcode: 2013shin.confE..89K Altcode: The magnetic field is the dominant force source in the solar coronal plasma, the one that shapes its structure. Synoptic observations that provide a direct information about the magnetic field have been recently became available by High Altitude Observatory (HAO) Coronal Multichannel Polarimeter (CoMP). The instrument provides linear polarization maps of the Fe XIII 10747 A 'forbidden' line. The observed linear polarization depends on magnetic field orientation through Hanle effect. These observation, supplied with additional photospheric magnetic field measurements and UV observations, are used for 3D reconstruction of the coronal magnetic field by applying the vector tomography technique. Title: The Chromosphere and Prominence Magnetometer Authors: de Wijn, Alfred; Bethge, Christian; McIntosh, Scott; Tomczyk, Steven; Burkepile, Joan Bibcode: 2013EGUGA..1512765D Altcode: The Chromosphere and Prominence Magnetometer (ChroMag) is a synoptic instrument with the goal of quantifying the intertwined dynamics and magnetism of the solar chromosphere and in prominences through imaging spectro-polarimetry of the full solar disk in a synoptic fashion. The picture of chromospheric magnetism and dynamics is rapidly developing, and a pressing need exists for breakthrough observations of chromospheric vector magnetic field measurements at the true lower boundary of the heliospheric system. ChroMag will provide measurements that will enable scientists to study and better understand the energetics of the solar atmosphere, how prominences are formed, how energy is stored in the magnetic field structure of the atmosphere and how it is released during space weather events like flares and coronal mass ejections. An essential part of the ChroMag program is a commitment to develop and provide community access to the `inversion' tools necessary to interpret the measurements and derive the magneto-hydrodynamic parameters of the plasma. Measurements of an instrument like ChroMag provide critical physical context for the Solar Dynamics Observatory (SDO) and Interface Region Imaging Spectrograph (IRIS) as well as ground-based observatories such as the future Advanced Technology Solar Telescope (ATST). A prototype is currently under construction at the High Altitude Observatory of the National Center for Atmospheric Research in Boulder, CO, USA. The heart of the ChroMag instrument is an electro-optically tunable wide-fielded narrow-band birefringent six-stage Lyot filter with a built-in polarimeter. We will present a progress update on the ChroMag design, and present results from the prototype instrument. Title: The Coronal Solar Magnetism Observatory Authors: Tomczyk, S. Bibcode: 2012IAUSS...6E.214T Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required to advance our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment. The central instrument in this suite is a 1.5-m aperture coronagraph. Additional instruments include a K-Coronagraph and a Chromospheric Magnetometer (ChroMag). We will present an overview of the COSMO project and give an update on the status, including: joint US/China engineering development of the 1.5-m coronagraph and its post-focus instrumentation; ongoing construction of the K-Coronagraph; development of a prototype filter/polarimeter for ChroMag; and recent progress in coronal field measurement with the prototype Coronal Multi-channel Polarimeter instrument. Title: Reconstruction of the 3D Coronal Magnetic Field by Vector Tomography with Infrared Spectropolarimetric Observations from CoMP Authors: Kramar, M.; Lin, H.; Tomczyk, S.; Davila, J. M.; Inhester, B. Bibcode: 2012AGUFMSH42A..06K Altcode: Magnetic fields determine the static and dynamic properties of the solar corona. A significant progress has been achieved in direct measurement of the magnetically sensitive coronal emission with deployment of the HAO Coronal Multichannel Polarimeter (CoMP). The instrument provides polarization measurements of Fe XIII 10747 A forbidden line emission. The observed polarization depends on magnetic field through the Hanle and Zeeman effects. However, because the coronal measurements are integrated over line-of-site (LOS), it is impossible to derive the configuration of the coronal magnetic field from a single observation (from a single viewing direction). The vector tomography techniques based on the infrared polarimetric measurements from several viewing directions has been developed in order to resolve the 3D coronal magnetic field structure over LOS. Because of the non-linear character of the Hanle effect, the reconstruction result based on such data is not straightforward and depends on the particular coronal field configuration. For several possible cases of coronal magnetic field configuration, it has been found that even just Stokes-Q and -U data (supplied with 3D coronal density and temperature) can be used in the vector tomography to provide a realistic 3D coronal magnetic field. The 3D coronal density and temperature needed as an supplemental input are reconstructed by the scalar field tomography method using ultraviolet observations from EUVI/STEREO. We will present the reconstructed 3D coronal density, temperature and magnetic field in the range of ∼ 1.3 R obtained by the scalar and vector tomography. Title: A Space Weather Mission to the Earth's 5th Lagrangian Point (L5) Authors: Howard, R. A.; Vourlidas, A.; Ko, Y.; Biesecker, D. A.; Krucker, S.; Murphy, N.; Bogdan, T. J.; St Cyr, O. C.; Davila, J. M.; Doschek, G. A.; Gopalswamy, N.; Korendyke, C. M.; Laming, J. M.; Liewer, P. C.; Lin, R. P.; Plunkett, S. P.; Socker, D. G.; Tomczyk, S.; Webb, D. F. Bibcode: 2012AGUFMSA13D..07H Altcode: The highly successful STEREO mission, launched by NASA in 2006, consisted of two spacecraft in heliocentric orbit, one leading and one trailing the Earth and each separating from Earth at the rate of about 22.5 degrees per year. Thus the two spacecraft have been probing different probe/Sun/Earth angles. The utility of having remote sensing and in-situ instrumentation away from the Sun-Earth line was well demonstrated by STEREO. Here we propose the concept of a mission at the 5th Lagrangian "point" in the Earth/Sun system, located behind Earth about 60 degrees to the East of the Sun-Earth line. Such a mission would enable many aspects affecting space weather to be well determined and thus improving the prediction of the conditions of the solar wind as it impinges on geospace. For example, Coronal Mass Ejections can tracked for a significant distance toward Earth, new active regions can be observed before they become visible to the Earth observer, the solar wind can be measured before it rotates to Earth. The advantages of such a mission will be discussed in this presentation. Title: Stray light and polarimetry considerations for the COSMO K-Coronagraph Authors: de Wijn, Alfred G.; Burkepile, Joan T.; Tomczyk, Steven; Nelson, Peter G.; Huang, Pei; Gallagher, Dennis Bibcode: 2012SPIE.8444E..3ND Altcode: 2012arXiv1207.0978D The COSMO K-Coronagraph is scheduled to replace the aging Mk4 K-Coronameter at the Mauna Loa Solar Observatory of the National Center for Atmospheric Research in 2013. We present briefly the science objectives and derived requirements, and the optical design. We single out two topics for more in-depth discussion: stray light, and performance of the camera and polarimeter. Title: Optical design of the COSMO large coronagraph Authors: Gallagher, Dennis; Tomczyk, Steven; Zhang, Haiying; Nelson, Peter G. Bibcode: 2012SPIE.8444E..3PG Altcode: The Coronal Solar Magnetism Observatory (COSMO) is a facility dedicated to measuring magnetic fields in the corona and chromosphere of the Sun. It will be located on a mountaintop in the Hawaiian Islands and will replace the current Mauna Loa Solar Observatory (MLSO). COSMO will employ a suite of instruments to determine the magnetic field and plasma conditions in the solar atmosphere and will enhance the value of data collected by other observatories on the ground (SOLIS, ATST, FASR) and in space (SDO, Hinode, SOHO, GOES, STEREO, DSCOVR, Solar Probe+, Solar Orbiter). The dynamics and energy flow in the corona are dominated by magnetic fields. To understand the formation of Coronal Mass Ejections (CMEs), their relation to other forms of solar activity, and their progression out into the solar wind requires measurements of coronal magnetic fields. The COSMO suite includes the Large Coronagraph (LC), the Chromosphere and Prominence Magnetometer (ChroMag) and the K-Coronagraph. The Large Coronagraph will employ a 1.5 meter fuse silica singlet lens and birefringent filters to measure magnetic fields out to two solar radii. It will observe over a wide range of wavelengths from 500 to 1100 nm providing the capability of observing a number of coronal, chromospheric, and photospheric emission lines. Of particular importance to measuring coronal magnetic fields are the forbidden emission lines of Fe XIII at 1074.7 nm and 1079.8 nm. These lines are faint and require the very large aperture. NCAR and NSF have provided funding to bring the COSMO Large Coronagraph to a preliminary design review (PDR) state by the end of 2013. Title: The chromosphere and prominence magnetometer Authors: de Wijn, Alfred G.; Bethge, Christian; Tomczyk, Steven; McIntosh, Scott Bibcode: 2012SPIE.8446E..78D Altcode: 2012arXiv1207.0969D The Chromosphere and Prominence Magnetometer (ChroMag) is conceived with the goal of quantifying the intertwined dynamics and magnetism of the solar chromosphere and in prominences through imaging spectro- polarimetry of the full solar disk. The picture of chromospheric magnetism and dynamics is rapidly developing, and a pressing need exists for breakthrough observations of chromospheric vector magnetic field measurements at the true lower boundary of the heliospheric system. ChroMag will provide measurements that will enable scientists to study and better understand the energetics of the solar atmosphere, how prominences are formed, how energy is stored in the magnetic field structure of the atmosphere and how it is released during space weather events like flares and coronal mass ejections. An integral part of the ChroMag program is a commitment to develop and provide community access to the "inversion" tools necessary for the difficult interpretation of the measurements and derive the magneto-hydrodynamic parameters of the plasma. Measurements of an instrument like ChroMag provide critical physical context for the Solar Dynamics Observatory (SDO) and Interface Region Imaging Spectrograph (IRIS) as well as ground-based observatories such as the future Advanced Technology Solar Telescope (ATST). Title: 3D Coronal Magnetic Field reconstructed by Vector Tomography Method using CoMP data Authors: Kramar, Maxim; Lin, H.; Tomczyk, S.; Inhester, B.; Davila, J. Bibcode: 2012shin.confE.141K Altcode: Magnetic fields in the solar corona dominates the gas pressure and therefore determine the static and dynamic properties of the corona. Direct measurement of the coronal magnetic field is one of the most challenging problems in observational solar astronomy and recently a significant progress has been achieved here with deployment of the HAO Coronal Multichannel Polarimeter (CoMP). The instrument provides polarization measurements of Fe XIII 10747 A forbidden line emission. The observed polarization depends on magnetic field through the Hanle and Zeeman effects. However, because the coronal measurements are integrated over line-of-site (LOS), it is impossible to derive the configuration of the coronal magnetic field from a single observation (from a single viewing direction). The vector tomography techniques based on measurements from several viewing directions has the potential to resolve the 3D coronal magnetic field structure over LOS. Because of the non-linear character of the Hanle effect, the reconstruction result based on such data is not straightforward and depends on the particular coronal field configuration. Therefore, previously we also studied what is the sensitivity of the vector tomographic inversion to various coronal magnetic field models. For several possible cases of coronal magnetic field configuration, it has been found that even just Stokes-Q and -U data (supplied with 3D coronal density and temperature) can be used in vector tomography to provide a realistic 3D coronal magnetic field configuration. The 3D coronal density and temperature needed as an supplemental input are reconstructed by the scalar field tomography method using ultraviolet observations from EUVI/STEREO. We will present the reconstructed 3D coronal magnetic field in the range of ∼1.3 R_⊙ obtained by the vector tomographic technique that has been applied to the CoMP data. Title: COSMO: A Facility Dedicated to the Measurement of Coronal Magnetic Fields Authors: Kolinski, Don J.; Gallagher, D.; Nelson, P.; Tomczyk, S.; Zhang, H. Bibcode: 2012shin.confE.100K Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. The COronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) in collaboration with the University of Hawaii. It will replace the current NCAR Mauna Loa Solar Observatory which has been collecting synoptic coronal data for over 40 years (http://mlso.hao.ucar.edu). COSMO will enhance the value of existing and new observatories on the ground (SOLIS, ATST, and FASR) and in space (e.g. SDO, STEREO, Hinode, SOHO, GOES, SP+, SO) by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. Title: The Chromospheric Magnetometer ChroMag Authors: Bethge, Christian; de Wijn, A. G.; McIntosh, S. W.; Tomczyk, S.; Casini, R. Bibcode: 2012AAS...22013506B Altcode: We present the Chromosphere Magnetometer (ChroMag), which is part of the Coronal Solar Magnetism Observatory (COSMO) proposed by the High Altitude Observatory (HAO) in collaboration with the University of Hawaii and the University of Michigan. ChroMag will perform routine measurements of chromospheric magnetic fields in a synoptic manner. A

prototype is currently being assembled at HAO. The main component of the instrument is a Lyot-type filtergraph polarimeter for both on-disk and off-limb polarization measurements in

the spectral lines of H alpha at 656.3 nm, Fe I 617.3 nm, Ca II 854.2 nm, He I 587.6 nm, and He I 1083.0 nm. The Lyot filter is tunable at a fast rate. This allows to determine line-of-sight

velocities in addition to the magnetic field measurements. The instrument has a field-of-view of up to 2.5 solar radii and will acquire data at a cadence of less than 1 minute and at a spatial resolution of 2 arcsec. The community will have open access to the data as well as to a set of inversion tools for an easier interpretation of the measurements. We show an overview of the proposed instrument and first results from the protoype. Title: Recent Results from the Coronal Multi-Channel Polarimeter Authors: Tomczyk, Steven; Bethge, C.; Gibson, S. E.; McIntosh, S. W.; Rachmeler, L. A.; Tian, H. Bibcode: 2012AAS...22031001T Altcode: The Coronal Multi-Channel Polarimeter (CoMP) instrument is a ground-based filter/polarimeter which can image the solar corona at wavelengths around the emission lines of FeXIII at 1074.7 and 1079.8 nm and the chromospheric emission line of HeI at 1083.0 nm. The instrument consists of a 20-cm aperture coronagraph followed by a Stokes polarimeter and a Lyot birefringent filter with a passband of 0.14 nm width. Both the polarimeter and filter employ liquid crystals for rapid electro-optical tuning. This instrument measures the line-of-sight strength of the coronal magnetic field through the Zeeman effect and the plane-of-sky direction of the magnetic field via resonance scattering. The line-of-sight velocity can also be determined from the Doppler shift. The CoMP has obtained daily observations from the Mauna Loa Solar Observatory for almost one year. We will present recent measurements of the polarization signatures seen with the CoMP and a comparison with models that allow us to constrain coronal structure. We also will present observations of coronal waves taken with the CoMP and discuss their implications for the heating of the solar corona and the acceleration of the solar wind. Title: The Coronal Solar Magnetism Observatory (COSMO) Authors: Tomczyk, Steven Bibcode: 2012AAS...22020211T Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required in our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. However, routine observations of the strength and orientation of coronal and chromospheric magnetic fields are not currently available. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment. We will present an overview of the COSMO and show recent progress in development of the COSMO observatory. Title: A First Look at Magnetic Field Data Products from SDO/HMI Authors: Liu, Y.; Scherrer, P. H.; Hoeksema, J. T.; Schou, J.; Bai, T.; Beck, J. G.; Bobra, M.; Bogart, R. S.; Bush, R. I.; Couvidat, S.; Hayashi, K.; Kosovichev, A. G.; Larson, T. P.; Rabello-Soares, C.; Sun, X.; Wachter, R.; Zhao, J.; Zhao, X. P.; Duvall, T. L., Jr.; DeRosa, M. L.; Schrijver, C. J.; Title, A. M.; Centeno, R.; Tomczyk, S.; Borrero, J. M.; Norton, A. A.; Barnes, G.; Crouch, A. D.; Leka, K. D.; Abbett, W. P.; Fisher, G. H.; Welsch, B. T.; Muglach, K.; Schuck, P. W.; Wiegelmann, T.; Turmon, M.; Linker, J. A.; Mikić, Z.; Riley, P.; Wu, S. T. Bibcode: 2012ASPC..455..337L Altcode: The Helioseismic and Magnetic Imager (HMI; Scherrer & Schou 2011) is one of the three instruments aboard the Solar Dynamics Observatory (SDO) that was launched on February 11, 2010 from Cape Canaveral, Florida. The instrument began to acquire science data on March 24. The regular operations started on May 1. HMI measures the Doppler velocity and line-of-sight magnetic field in the photosphere at a cadence of 45 seconds, and the vector magnetic field at a 135-second cadence, with a 4096× 4096 pixels full disk coverage. The vector magnetic field data is usually averaged over 720 seconds to suppress the p-modes and increase the signal-to-noise ratio. The spatial sampling is about 0".5 per pixel. HMI observes the Fe i 6173 Å absorption line, which has a Landé factor of 2.5. These data are further used to produce higher level data products through the pipeline at the HMI-AIA Joint Science Operations Center (JSOC) - Science Data Processing (Scherrer et al. 2011) at Stanford University. In this paper, we briefly describe the data products, and demonstrate the performance of the HMI instrument. We conclude that the HMI is working extremely well. Title: Solar magnetism eXplorer (SolmeX). Exploring the magnetic field in the upper atmosphere of our closest star Authors: Peter, Hardi; Abbo, L.; Andretta, V.; Auchère, F.; Bemporad, A.; Berrilli, F.; Bommier, V.; Braukhane, A.; Casini, R.; Curdt, W.; Davila, J.; Dittus, H.; Fineschi, S.; Fludra, A.; Gandorfer, A.; Griffin, D.; Inhester, B.; Lagg, A.; Landi Degl'Innocenti, E.; Maiwald, V.; Sainz, R. Manso; Martínez Pillet, V; Matthews, S.; Moses, D.; Parenti, S.; Pietarila, A.; Quantius, D.; Raouafi, N. -E.; Raymond, J.; Rochus, P.; Romberg, O.; Schlotterer, M.; Schühle, U.; Solanki, S.; Spadaro, D.; Teriaca, L.; Tomczyk, S.; Trujillo Bueno, J.; Vial, J. -C. Bibcode: 2012ExA....33..271P Altcode: 2011arXiv1108.5304P; 2011ExA...tmp..134P The magnetic field plays a pivotal role in many fields of Astrophysics. This is especially true for the physics of the solar atmosphere. Measuring the magnetic field in the upper solar atmosphere is crucial to understand the nature of the underlying physical processes that drive the violent dynamics of the solar corona—that can also affect life on Earth. SolmeX, a fully equipped solar space observatory for remote-sensing observations, will provide the first comprehensive measurements of the strength and direction of the magnetic field in the upper solar atmosphere. The mission consists of two spacecraft, one carrying the instruments, and another one in formation flight at a distance of about 200 m carrying the occulter to provide an artificial total solar eclipse. This will ensure high-quality coronagraphic observations above the solar limb. SolmeX integrates two spectro-polarimetric coronagraphs for off-limb observations, one in the EUV and one in the IR, and three instruments for observations on the disk. The latter comprises one imaging polarimeter in the EUV for coronal studies, a spectro-polarimeter in the EUV to investigate the low corona, and an imaging spectro-polarimeter in the UV for chromospheric studies. SOHO and other existing missions have investigated the emission of the upper atmosphere in detail (not considering polarization), and as this will be the case also for missions planned for the near future. Therefore it is timely that SolmeX provides the final piece of the observational quest by measuring the magnetic field in the upper atmosphere through polarimetric observations. Title: Constraints on coronal magnetic fields from observations of visible and IR emission lines Authors: Tomczyk, Steven Bibcode: 2012decs.confE.116T Altcode: Information on the strength and direction of coronal magnetic fields can be obtained from the observation of the polarization of visible and IR emission lines. These observations are confined to the corona above the solar limb and integrated along the line-of-sight. A wealth of information is also available through the analysis of the waves that permeate the corona as observed in line-of-sight velocity measurements. I will present an overview of the strengths and weaknesses of techniques for extracting information on coronal magnetism from these sources, and present an assessment for future progress in this area. Title: The Chromosphere and Prominence Magnetometer Authors: de Wijn, Alfred; Bethge, Christian; McIntosh, Scott; Tomczyk, Steven; Casini, Roberto Bibcode: 2012decs.confE..63D Altcode: ChroMag is an imaging polarimeter designed to measure on-disk chromosphere and off-disk prominence magnetic fields using the spectral lines of He I (587.6 and 1083 nm). It is part of the planned CoSMO suite, which includes two more instruments: a large 1.5-m refracting coronagraph for coronal magnetic field measurements, and the K-Coronagraph for measurement of the coronal density. ChroMag will provide insights in the energetics of the solar atmosphere, how prominences are formed, and how energy is stored and released in the magnetic field structure of the atmosphere. An essential part of the ChroMag program is a commitment to develop and provide community access to the "inversion" tools necessary to interpret the measurements and derive the magneto-hydrodynamic parameters of the plasma. A prototype instrument is currently under construction at the High Altitude Observatory. We will present an overview of the ChroMag instrument concept, target science, and prototype status. Title: Synoptic measurements of chromospheric and prominence magnetic fields with the Chromosphere Magnetometer ChroMag Authors: Bethge, C.; de Wijn, A. G.; McIntosh, S. W.; Tomczyk, S.; Casini, R. Bibcode: 2012decs.confE..62B Altcode: The Chromosphere Magnetometer is part of the Coronal Solar Magnetism Observatory (COSMO) proposed by the High Altitude Observatory (HAO) in collaboration with the University of Hawaii and the University of Michigan. Routine measurements of chromospheric and coronal magnetic fields are vital if we want to understand fundamental problems like the energy and mass balance of the corona, the onset and acceleration of the solar wind, the emergence of CMEs, and how these phenomena influence space weather. ChroMag is designed as a Lyot-type filtergraph polarimeter with an FOV of 2.5 solar radii, i.e., it will be capable of both on-disk and off-limb polarimetric measurements. The Lyot filter - currently being built at HAO - is tunable at a fast rate, which allows to determine line-of-sight velocities. This will be done in the spectral lines of H alpha at 656.3 nm, Fe I 617.3 nm, Ca II 854.2 nm, He I 587.6 nm, and He I 1083.0 nm at a high cadence of less than 1 minute, and at a moderate spatial resolution of 2 arcsec. ChroMag data will be freely accessible to the community, along with inversion tools for an easier interpretation of the data. A protoype instrument for ChroMag is currently being assembled at HAO and is expected to perform first measurements at the Boulder Mesa Lab in Summer 2012. We present an overview of the ChroMag instrument and the current status of the protoype. Title: Polarization Calibration of the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) Authors: Schou, J.; Borrero, J. M.; Norton, A. A.; Tomczyk, S.; Elmore, D.; Card, G. L. Bibcode: 2012SoPh..275..327S Altcode: As part of the overall ground-based calibration of the Helioseismic and Magnetic Imager (HMI) instrument an extensive set of polarimetric calibrations were performed. This paper describes the polarimetric design of the instrument, the test setup, the polarimetric model, the tests performed, and some results. It is demonstrated that HMI achieves an accuracy of 1% or better on the crosstalks between Q, U, and V and that our model can reproduce the intensities in our calibration sequences to about 0.4%. The amount of depolarization is negligible when the instrument is operated as intended which, combined with the flexibility of the polarimeter design, means that the polarimetric efficiency is excellent. Title: Design and Ground Calibration of the Helioseismic and Magnetic Imager (HMI) Instrument on the Solar Dynamics Observatory (SDO) Authors: Schou, J.; Scherrer, P. H.; Bush, R. I.; Wachter, R.; Couvidat, S.; Rabello-Soares, M. C.; Bogart, R. S.; Hoeksema, J. T.; Liu, Y.; Duvall, T. L.; Akin, D. J.; Allard, B. A.; Miles, J. W.; Rairden, R.; Shine, R. A.; Tarbell, T. D.; Title, A. M.; Wolfson, C. J.; Elmore, D. F.; Norton, A. A.; Tomczyk, S. Bibcode: 2012SoPh..275..229S Altcode: The Helioseismic and Magnetic Imager (HMI) investigation (Solar Phys. doi:10.1007/s11207-011-9834-2, 2011) will study the solar interior using helioseismic techniques as well as the magnetic field near the solar surface. The HMI instrument is part of the Solar Dynamics Observatory (SDO) that was launched on 11 February 2010. The instrument is designed to measure the Doppler shift, intensity, and vector magnetic field at the solar photosphere using the 6173 Å Fe I absorption line. The instrument consists of a front-window filter, a telescope, a set of waveplates for polarimetry, an image-stabilization system, a blocking filter, a five-stage Lyot filter with one tunable element, two wide-field tunable Michelson interferometers, a pair of 40962 pixel cameras with independent shutters, and associated electronics. Each camera takes a full-disk image roughly every 3.75 seconds giving an overall cadence of 45 seconds for the Doppler, intensity, and line-of-sight magnetic-field measurements and a slower cadence for the full vector magnetic field. This article describes the design of the HMI instrument and provides an overview of the pre-launch calibration efforts. Overviews of the investigation, details of the calibrations, data handling, and the science analysis are provided in accompanying articles. Title: The Helioseismic and Magnetic Imager (HMI) Investigation for the Solar Dynamics Observatory (SDO) Authors: Scherrer, P. H.; Schou, J.; Bush, R. I.; Kosovichev, A. G.; Bogart, R. S.; Hoeksema, J. T.; Liu, Y.; Duvall, T. L.; Zhao, J.; Title, A. M.; Schrijver, C. J.; Tarbell, T. D.; Tomczyk, S. Bibcode: 2012SoPh..275..207S Altcode: The Helioseismic and Magnetic Imager (HMI) instrument and investigation as a part of the NASA Solar Dynamics Observatory (SDO) is designed to study convection-zone dynamics and the solar dynamo, the origin and evolution of sunspots, active regions, and complexes of activity, the sources and drivers of solar magnetic activity and disturbances, links between the internal processes and dynamics of the corona and heliosphere, and precursors of solar disturbances for space-weather forecasts. A brief overview of the instrument, investigation objectives, and standard data products is presented. Title: The Coronal Solar Magnetism Observatory (COSMO) Authors: Tomczyk, S. Bibcode: 2011AGUFMSH43B1952T Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required in our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. However, routine observations of the strength and orientation of coronal and chromospheric magnetic fields are not currently available. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment. We will present the capabilities of the COSMO and discuss recent progress in these measurements with the prototype Coronal Multi-channel Polarimeter (CoMP) instrument. Title: Vector Tomography Inversion for the 3D Coronal Magnetic Field Based on CoMP data Authors: Kramar, M.; Lin, H.; Tomczyk, S.; Inhester, B.; Davila, J. M. Bibcode: 2011AGUFMSH43B1948K Altcode: Magnetic fields in the solar corona dominates the gas pressure and therefore determine the static and dynamic properties of the corona. Direct measurement of the coronal magnetic field is one of the most challenging problems in observational solar astronomy and recently a significant progress has been achieved here with deployment of the HAO Coronal Multichannel Polarimeter (CoMP). The instrument provides polarization measurements of Fe XIII 10747 A forbidden line emission. The observed polarization depends on magnetic field through the Hanle and Zeeman effects. However, because the coronal measurements are integrated over line-of-site (LOS), it is impossible to derive the configuration of the coronal magnetic field from a single observation (from a single viewing direction). The vector tomography techniques based on measurements from several viewing directions has the potential to resolve the 3D coronal magnetic field structure over LOS. Because of the non-linear character of the Hanle effect, the reconstruction result based on such data is not straightforward and depends on the particular coronal field configuration. Therefore we study here what is the sensitivity of the vector tomographic inversion to sophisticated (MHD) coronal magnetic field models. For several important cases of magnetic field configuration, it has been found that even just Stokes-Q and -U data (supplied with 3D coronal density and temperature) can be used in vector tomography to provide a realistic 3D coronal magnetic field configuration. This vector tomograpic technique is applied to CoMP data. Title: Comparing Global Coronal Models to CoMP Data Authors: Rachmeler, L. A.; Gibson, S. E.; Tomczyk, S. Bibcode: 2011AGUFMSH43B1941R Altcode: Coronal polarization data is one of the very few available quantitative measurements of the coronal magnetic field, which makes it extremely attractive as a means of validating numerical models. Our forward analysis technique produces synthetic line-of-sight integrated polarization signals from coronal models. We present initial results from comparisons of forward calculations of the Potential Field Source Surface (PFSS) model to polarization data taken with the Coronal Multichannel Polarimeter (CoMP). This research focuses on validating the applicability of the PFSS model by determining how much the real corona deviates from a potential field. The non-potentiality of the corona not only has applications for testing the PFSS field, but also for forecasting, and for finding the locations of greatest magnetic energy storage. Title: HMI vector magnetic field products: the long-awaited release has come! Now what? Authors: Centeno, R.; Barnes, G.; Borrero, J.; Couvidat, S. P.; Hayashi, K.; Hoeksema, J. T.; Leka, K. D.; Liu, Y.; Schou, J.; Schuck, P. W.; Sun, X.; Tomczyk, S. Bibcode: 2011AGUFMSH31A1985C Altcode: HMI vector magnetic field test products will be released, alongside with the corresponding documentation, soon after the submission of this abstract. These data represent a stage of the project at which the HMI vector team has a large degree of confidence in the results. However, longer-term research topics on how to improve certain aspects of the data pipeline in general -and the spectral line inversion code in particular- are being pursued as we get valuable input from the user community. I will give a brief summary of the characteristics of the released inversion data products and an update of where we stand now. Title: VFISV: Very Fast Inversion of the Stokes Vector for the Helioseismic and Magnetic Imager Authors: Borrero, J. M.; Tomczyk, S.; Kubo, M.; Socas-Navarro, H.; Schou, J.; Couvidat, S.; Bogart, R. Bibcode: 2011SoPh..273..267B Altcode: 2009arXiv0901.2702B In this paper we describe in detail the implementation and main properties of a new inversion code for the polarized radiative transfer equation (VFISV: Very Fast Inversion of the Stokes Vector). VFISV will routinely analyze pipeline data from the Helioseismic and Magnetic Imager (HMI) on-board of the Solar Dynamics Observatory (SDO). It will provide full-disk maps (4096×4096 pixels) of the magnetic field vector on the Solar Photosphere every ten minutes. For this reason VFISV is optimized to achieve an inversion speed that will allow it to invert sixteen million pixels every ten minutes with a modest number (approx. 50) of CPUs. Here we focus on describing a number of important details, simplifications and tweaks that have allowed us to significantly speed up the inversion process. We also give details on tests performed with data from the spectropolarimeter on-board of the Hinode spacecraft. Title: Wavelength-diverse Polarization Modulators for Stokes Polarimetry Authors: de Wijn, A. G.; Tomczyk, S.; Casini, R.; Nelson, P. G. Bibcode: 2011ASPC..437..413D Altcode: An increasing number of astronomical applications depend on the measurement of polarized light. For example, our knowledge of solar magnetism relies heavily on our ability to measure and interpret polarization signatures introduced by magnetic field. Many new instruments have consequently focused considerable attention on polarimetry. For solar applications, spectro-polarimeters in particular are often designed to observe the solar atmosphere in multiple spectral lines simultaneously, thus requiring that the polarization modulator employed is efficient at all wavelengths of interest. We present designs of polarization modulators that exhibit near-optimal modulation characteristics over broad spectral ranges. Our design process employs a computer code to optimize the efficiency of the modulator at specified wavelengths. We will present several examples of modulator designs based on rotating stacks of Quartz waveplates and ferroelectric liquid crystals (FLCs). An FLC-based modulator of this design was recently deployed for the ProMag instrument at the Evans Solar Facility of NSO/SP. Title: HMI: First Results Authors: Centeno, R.; Tomczyk, S.; Borrero, J. M.; Couvidat, S. Hayashi, K.; Hoeksema, T.; Liu, Y.; Schou, J. Bibcode: 2011ASPC..437..147C Altcode: 2010arXiv1012.3796C The Helioseismic and Magnetic Imager (HMI) has just started producing data that will help determine what the sources and mechanisms of variability in the Sun's interior are. The instrument measures the Doppler shift and the polarization of the Fe I 6173 Å line, on the entire solar disk at a relatively-high cadence, in order to study the oscillations and the evolution of the full vector magnetic field of the solar Photosphere. After the data are properly calibrated, they are given to a Milne-Eddington inversion code (VFISV, Borrero et al. 2010) whose purpose is to infer certain aspects of the physical conditions in the Sun's Photosphere, such as the full 3-D topology of the magnetic field and the line-of-sight velocity at the solar surface. We will briefly describe the characteristics of the inversion code, its advantages and limitations -both in the context of the model atmosphere and the actual nature of the data-, and other aspects of its performance on such a remarkable data load. Also, a cross-comparison with near-simultaneous maps from the Spectro-Polarimeter (SP) onboard Hinode will be made. Title: A Ring of Polarized Light: Evidence for Twisted Coronal Magnetism in Cavities Authors: Dove, J. B.; Gibson, S. E.; Rachmeler, L. A.; Tomczyk, S.; Judge, P. Bibcode: 2011ApJ...731L...1D Altcode: Coronal prominence cavities may be manifestations of twisted or sheared magnetic fields capable of storing the energy required to drive solar eruptions. The Coronal Multi-Channel Polarimeter (CoMP), recently installed at Mauna Loa Solar Observatory, can measure polarimetric signatures of current-carrying magnetohydrodynamic (MHD) systems. For the first time, this instrument offers the capability of daily full-Sun observations of the forbidden lines of Fe XIII with high enough spatial resolution and throughput to measure polarimetric signatures of current-carrying MHD systems. By forward-calculating CoMP observables from analytic MHD models of spheromak-type magnetic flux ropes, we show that a predicted observable for such flux ropes oriented along the line of sight is a bright ring of linear polarization surrounding a region where the linear polarization strength is relatively depleted. We present CoMP observations of a coronal cavity possessing such a polarization ring. Title: Koronálny multikanálový polarimeter pre observatórium Lomnický štít Title: Koronálny multikanálový polarimeter pre observatórium Lomnický štít Title: Coronal multichannel polarimeter for Lomnický štít Observatory. Authors: Rybák, J.; Ambróz, J.; Gömöry, P.; Kozák, M.; Kučera, A.; Tomczyk, S.; Sewell, S.; Summers, R.; Sutherland, L.; Watt, A. Bibcode: 2010nspm.conf..196R Altcode: The contribution presents the process of development and preparation of the Coronal Multi-channel Polarimeter (COMP-S) for the Lomnický štít Observatory of the SAS Astronomy Institute. The design of the device is based on the experience gained in recent years with the CoMP (High Altitude Observatory / NCAR; Boulder, USA) instrument. The device will be a combination of two main optical components: the Lyot tunable filter and polarimeter, and is prepared specifically for one of the 20 cm Zeiss coronagraph at the Lomnický štít Observatory where it will be installed in 2011. CoMP-S will differ from its predecessor in several respects. The most important difference is that CoMP-S will be able to observe the corona and chromospheric emission lines in the wavelength range from 530 to 1083 nm. This feature will be achieved using superachromatic wave plates and dichroic polarizers with wide bandwidth. Furthermore, in the CoMP-S instrument new SWIFT liquid crystals of Meadowlark Optics company will be used as variable retarders instead of nematic liquid crystal retarders (LCVR) which will considerably shorten the measuring process. Ferroelectric liquid crystals will provide measurements of the full Stokes vector with nearly optimal polarization throughout the whole instrument bandwidth. Recently developed sCMOS cameras are to provide diffraction limit resolution of observations, with the 860x680 arc second field and 30-frames-per-second cadence. The device will be used in the Astronomical Observatory of SAS at Lomnický štít primarily for spectrum polarimetry of prominences and coronal loops of the active solar regions. Title: A ring of polarized light: evidence for twisted coronal magnetism in cavities (Invited) Authors: Dove, J.; Rachmeler, L.; Gibson, S. E.; Judge, P. G.; Tomczyk, S. Bibcode: 2010AGUFMSH54A..01D Altcode: Determining coronal magnetic fields is crucial to modeling the processes that power and trigger solar flares and coronal mass ejections. Coronal prominence cavities have been modeled as magnetic flux ropes, and have been observed to erupt bodily as coronal mass ejections. One promising technique for establishing the magnetic morphology of cavities is to use spectropolarimetry of the infrared (IR) forbidden lines of Fe XIII (at 1074.7 nm and 1079.8 nm). The Coronal Multi-Channel Polarimeter is currently situated at the Mauna Loa Solar Observatory (MLSO), and has begun taking daily full-Sun observations of line-of-sight integrated Stokes parameters for these lines. For a variety of analytic coronal magnetohydrodynamic models, we have determined forward-calculations of CoMP observables using the formalism of Judge and Casini (2001). We show that different MHD models and orientations do yield distinguishing observational characteristics. In particular, a common characteristic for spheroidal flux ropes oriented along the observational line of sight is a ring of linear polarization surrounding a region where the linear polarization strength is relatively depleted (the heart of darkness). Such a polarization ring has been found in an observation of a coronal cavity taken by CoMP in April 2005 from Sacramento Peak. Cavities are ubiquitous features, particularly at this time of the solar cycle. The daily observations to be taken by CoMP at MLSO will allow us to further probe these structures, constraining models of coronal magnetism and providing a testbed for future capabilities of the proposed Coronal Solar Magnetism Observatory (COSMO). Title: The polychromatic polarization modulator Authors: de Wijn, Alfred G.; Tomczyk, Steven; Casini, Roberto; Nelson, Peter G. Bibcode: 2010SPIE.7735E..4AD Altcode: 2010SPIE.7735E.143D An increasing number of astronomical applications depend on the measurement of polarized light. For example, our knowledge of solar magnetism relies heavily on our ability to measure and interpret polarization signatures introduced by magnetic field. Many new instruments have consequently focused considerable attention on polarimetry. For solar applications, spectro-polarimeters in particular are often designed to observe the solar atmosphere in multiple spectral lines simultaneously, thus requiring that the polarization modulator employed is efficient at all wavelengths of interest. We present designs of polarization modulators that exhibit near-optimal modulation characteristics over broad spectral ranges. Our design process employs a computer code to optimize the efficiency of the modulator at specified wavelengths. We will present several examples of modulator designs based on rotating stacks of Quartz waveplates and Ferroelectric Liquid Crystals (FLCs). An FLC-based modulator of this design was recently deployed for the ProMag instrument at the Evans Solar Facility of NSO/SP. We show that this modulator behaves according to its design. Title: Wavelength-diverse polarization modulators for Stokes polarimetry Authors: Tomczyk, Steven; Casini, Roberto; de Wijn, Alfred G.; Nelson, Peter G. Bibcode: 2010ApOpt..49.3580T Altcode: 2010arXiv1006.3581T Information about the three-dimensional structure of solar magnetic fields is encoded in the polarized spectra of solar radiation by a host of physical processes. To extract this information, solar spectra must be obtained in a variety of magnetically sensitive spectral lines at high spatial, spectral, and temporal resolution with high precision. The need to observe many different spectral lines drives the development of Stokes polarimeters with a high degree of wavelength diversity. We present a new paradigm for the design of polarization modulators that operate over a wide wavelength range with near optimal polarimetric efficiency and are directly applicable to the next generation of multi-line Stokes polarimeters. These modulators are not achromatic in the usual sense because their polarimetric properties vary with wavelength, but they do so in an optimal way. Thus we refer to these modulators as polychromatic. We present here the theory behind polychromatic modulators, illustrate the concept with design examples, and present the performance properties of a prototype polychromatic modulator. Title: New Observations Of The Solar Coronal Magnetism And Waves With HAO/CoMP Authors: McIntosh, Scott W.; Tomczyk, S. Bibcode: 2010AAS...21630201M Altcode: We will present details of the observations made by the HAO Coronal Multi-channel Polarimeter (CoMP) following its recent deployment at the Mauna Loa Solar Observatory. As well as presenting the synoptic data products, measurements, and data access we will discuss monitoring of solar coronal magnetism, its evolution and MHD wave properties with this unique instrumentation. Title: Large-Scale Flows in Prominence Cavities Authors: Schmit, D. J.; Gibson, S. E.; Tomczyk, S.; Reeves, K. K.; Sterling, Alphonse C.; Brooks, D. H.; Williams, D. R.; Tripathi, D. Bibcode: 2009ApJ...700L..96S Altcode: Regions of rarefied density often form cavities above quiescent prominences. We observed two different cavities with the Coronal Multichannel Polarimeter on 2005 April 21 and with Hinode/EIS on 2008 November 8. Inside both of these cavities, we find coherent velocity structures based on spectral Doppler shifts. These flows have speeds of 5-10 km s-1, occur over length scales of tens of megameters, and persist for at least 1 hr. Flows in cavities are an example of the nonstatic nature of quiescent structures in the solar atmosphere. Title: Time-Distance Seismology of the Solar Corona with CoMP Authors: Tomczyk, Steven; McIntosh, Scott W. Bibcode: 2009ApJ...697.1384T Altcode: 2009arXiv0903.2002T We employ a sequence of Doppler images obtained with the Coronal Multi-channel Polarimeter (CoMP) instrument to perform time-distance seismology of the solar corona. We construct the first k-ω diagrams of the region. These allow us to separate outward and inward propagating waves and estimate the spatial variation of the plane-of-sky-projected phase speed, and the relative amount of outward and inward directed wave power. The disparity between outward and inward wave power and the slope of the observed power-law spectrum indicate that low-frequency Alfvénic motions suffer significant attenuation as they propagate, consistent with isotropic MHD turbulence. Title: Reconciling Chromospheric and Coronal Observations of Alfvenic Waves Authors: McIntosh, Scott W.; De Pontieu, B.; Tomczyk, S. Bibcode: 2009SPD....40.1303M Altcode: We review the properties of the Alfvenic waves that were discovered with Hinode/SOT and that have been shown to permeate the upper chromosphere. Statistical analysis shows that, if they penetrate into the corona, these waves carry enough energy to impact the energy balance of the solar wind and quiet Sun corona. However, CoMP observations of Alfven waves show much smaller resolved amplitudes than would be expected from the leakage of chromospheric waves into the corona. We use Monte Carlo simulations to show that line-of-sight superposition of a mix of Alfvenic waves with properties similar to those observed with Hinode/SOT and CoMP can reproduce the low wave amplitudes and enhanced non-thermal line broadening observed with CoMP. Our analysis indicates that the CoMP observations are compatible with a scenario in which low-frequency Alfvenic waves are responsible for a large fraction of the non-thermal broadening seen in the corona although some portion remains from the power spectrum of the wave generation process. This suggests that the flux carried by Alfvenic waves, in the finely structured corona, is significant enough to impact the energy balance of the corona and solar wind. Title: Flows and Plasma Properties in Quiescent Cavities Authors: Schmit, Donald; Gibson, S.; Reeves, K.; Sterling, A.; Tomczyk, S. Bibcode: 2009SPD....40.1015S Altcode: Regions of rarefied density often form cavities above quiescent prominences. In an attempt to constrain the plasma properties of "equilibrium" cavities we conduct several diagnostics using Hinode/EIS, STEREO/EUVI, and CoMP. One novel observation is of large scale flows in cavities. Using different instruments to observe two distinct cavities off the solar limb in coronal emission lines, we find that spectral doppler shifts imply LOS velocities within cavities on the order of 1-10 km/s. These flows occur over length scales of several hundred Mm and persist for hours. Title: Magnetically driven activity in the solar corona: a path to understanding the energetics of astrophysical plasmas Authors: Gibson, Sarah; Bastian, Tim; Lin, Haoscheng; Low, B. C.; Tomczyk Bibcode: 2009astro2010S..94G Altcode: No abstract at ADS Title: Time Distance Coronal Seismology With the CoMP Instrument Authors: Tomczyk, S.; McIntosh, S. Bibcode: 2008AGUFMSH11A..01T Altcode: Recent velocity imaging observations obtained with the Coronal Multi-channel Polarimeter (CoMP) instrument reveal the existence of ubiquitous propagating Alfvén waves in the solar corona. These data present an exciting opportunity for probing the structure and magnetic topology of the coronal plasma through coronal seismology. We present the results of a time-distance analysis of the wave observations which allows the determination of the phase speed of the waves and the relative quantity of outward and inward wave flux. This analysis also provides a k-omega diagnostic diagram of coronal waves. We discuss current and future prospects for coronal seismology with these data. Title: A Coherence-Based Approach for Tracking Waves in the Solar Corona Authors: McIntosh, Scott W.; De Pontieu, Bart; Tomczyk, Steven Bibcode: 2008SoPh..252..321M Altcode: 2008arXiv0808.2978M; 2008SoPh..tmp..162M We consider the problem of automatically (and robustly) isolating and extracting information about waves and oscillations observed in EUV image sequences of the solar corona with a view to near real-time application to data from the Atmospheric Imaging Array (AIA) on the Solar Dynamics Observatory (SDO). We find that a simple coherence/travel-time based approach detects and provides a wealth of information on transverse and longitudinal wave phenomena in the test sequences provided by the Transition Region and Coronal Explorer (TRACE). The results of the search are pruned (based on diagnostic errors) to minimize false-detections such that the remainder provides robust measurements of waves in the solar corona, with the calculated propagation speed allowing automated distinction between various wave modes. In this paper we discuss the technique, present results on the TRACE test sequences, and describe how our method can be used to automatically process the enormous flow of data (≈1 Tb day−1) that will be provided by SDO/AIA. Title: A new spectro-polarimeter for solar prominence and filament magnetic field measurements Authors: Elmore, David F.; Casini, Roberto; Card, Greg L.; Davis, Marc; Lecinski, Alice; Lull, Ron; Nelson, Peter G.; Tomczyk, Steven Bibcode: 2008SPIE.7014E..16E Altcode: 2008SPIE.7014E..39E We are constructing a spectro-­polarimeter using the 40-­cm coronagraph at the Evans Solar Facility of the National Solar Observatory in Sunspot, NM for the purpose of measuring the vector magnetic field in prominences and filaments. The Prominence Magnetometer (ProMag) is comprised of a polarization modulation package and a spectrograph. The modulation optics are located at the prime focus of the coronagraph along with calibration optics and a beamsplitter that creates two beams of orthogonal Stokes states. The spectrograph resides at the coude focus of the coronagraph. The polarizations of the two chromospheric lines of neutral helium, at 587.6 nm and 1083.0 nm, are to be observed simultaneously. We present details of the design of the spectro-­polarimeter. Title: The feasibility of large refracting telescopes for solar coronal research Authors: Nelson, Peter G.; Tomczyk, Steven; Elmore, David F.; Kolinski, Donald J. Bibcode: 2008SPIE.7012E..31N Altcode: 2008SPIE.7012E.104N Measuring magnetic fields in the solar corona requires a large aperture telescope with exceptionally low levels of scattered light. For internally-occulted coronagraphs the main source is scattering from dust or microroughness on the primary lens or mirror. We show refracting primaries offer significantly lower levels for both sources. To observe magnetic fields in the solar corona with scientifically interesting spatial and temporal resolutions, a 1 meter aperture or larger is required. For a long time such large-scale refractors have been deemed impractical or impossible to construct due to gravitational deformation of the lens. We present the results of finite-element and optical analyses of the gravitational deformation, stress-induced birefringence, and absorptive heating of a (see manuscript)1.5 meter f/5 fused silica lens. These studies demonstrate the traditional objections to large refractors are unfounded and large refracting primaries have unique capabilities. Title: Multi-wavelength Comparison of Prominence Cavities Authors: Schmit, D. J.; Gibson, S.; de Toma, G.; Reeves, K.; Tripathi, D.; Kucera, T.; Marque, C.; Tomczyk, S. Bibcode: 2008AGUSMSP43B..04S Altcode: Recent observational campaigns have brought together a wealth of data specifically designed to explore the physical properties and dynamics of prominence cavities. In particular, STEREO and Hinode data have provided new perspectives on these structures. In order to effectively analyze the data in a cohesive manner, we produce overlays of several distinct and complimentary datasets including SOHO UVCS, CDS, and EIT, Hinode SOT and EIS, STEREO SECCHI, TRACE, and Nancay Radioheliograph data as well as new observations of coronal magnetic fields in cavities from the Coronal Multichannel Polarimeter. We are thus able to investigate how sensitive morphology is to the wavelength observed which details the nature of the plasma in the cavity. Title: An Instrument to Measure Coronal Emission Line Polarization Authors: Tomczyk, S.; Card, G. L.; Darnell, T.; Elmore, D. F.; Lull, R.; Nelson, P. G.; Streander, K. V.; Burkepile, J.; Casini, R.; Judge, P. G. Bibcode: 2008SoPh..247..411T Altcode: 2008SoPh..tmp....3T We have constructed an instrument to measure the polarization of light emitted by the solar corona in order to constrain the strength and orientation of coronal magnetic fields. We call this instrument the Coronal Multichannel Polarimeter (CoMP). The CoMP is integrated into the Coronal One Shot coronagraph at Sacramento Peak Observatory and employs a combination birefringent filter and polarimeter to form images in two wavelengths simultaneously over a 2.8R field of view. The CoMP measures the complete polarization state at the 1074.7 and 1079.8 Fe XIII coronal emission lines, and the 1083.0 nm He I chromospheric line. In this paper we present design drivers for the instrument, provide a detailed description of the instrument, describe the calibration methodology, and present some sample data along with estimates of the uncertainty of the measured magnetic field. Title: The COronal Solar Magnetism Observatory Authors: Burkepile, J.; Tomczyk, S.; Lin, H.; Zurbuchen, T.; Judge, P.; Casini, R. Bibcode: 2007AGUFMSH53A1070B Altcode: Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. The COronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment. The facility consists of 3 instruments: 1) a meter-class aperture coronal magnetometer devoted to obtaining the highest quality polarimetric data of forbidden lines of Fe XIII 1074.7 and 1079.8 nm.; 2) a chromosphere and prominence magnetometer devoted primarily to measurements of lines of helium (D3, 1083 nm) and perhaps Halpha, that will provide full disk vector magnetic field observations; 3) a white-light polarized-brightness (pB) coronagraph that will observe down to 1.05 solar radii at very high time cadence (15 seconds) at high signal-to-noise. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) in collaboration with the University of Hawaii and the University of Michigan. COSMO will enhance the value of existing and new observatories on the ground (SOLIS, ATST, and FASR) and in space (SOHO, TRACE, GOES, SOLAR-B, STEREO, SDO) by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. Title: Alfven Waves in the Solar Corona Authors: Tomczyk, S.; McIntosh, S. W.; Keil, S. L.; Judge, P. G.; Schad, T.; Seeley, D. H.; Edmondson, J. Bibcode: 2007AGUFMSH21A0289T Altcode: We present observations of the coronal intensity, line-of-sight velocity, and linear polarization obtained in the FeXIII 1074.7 nm coronal emission line with the Coronal Multi-channel Polarimeter (CoMP) instrument. Analysis of these observations reveal ubiquitous upward propagating waves with phase speeds of 1-4 Mm/s and trajectories consistent with the direction of the magnetic field inferred from the linear polarization measurements. We can definitively identify these as Alfvén waves. An estimate of the energy carried by the waves that we spatially resolve indicates that they are unable to heat the solar corona, however, unresolved waves may carry sufficient energy. Title: Observing the Influence of Alfven Waves on the Energetics of the Quiet Solar Corona and Solar Wind Authors: McIntosh, S. W.; de Pontieu, B.; Tomczyk, S. Bibcode: 2007AGUFMSH21A0288M Altcode: We will present and discuss recent observations of Alfvén waves in the solar chromosphere, from the Solar Optical Telescope (SOT) on Hinode, and in the corona, from HAO's ground-based Coronal Multi-channel Polarimeter (CoMP). These observations unambiguously demonstrate, for the first time, that the magnetic chromosphere and corona are riddled with 3- and 5-minute (3-5mHz) Alfvénic oscillations predominantly propagating outward into the heliosphere. The combined analysis of these observations, augmented by spectroscopic data from SOHO/SUMER, provide a compelling look at the influence and importance of ubiquitously driven Alfvén waves in heating the quiet solar corona and driving the solar wind. Indeed, we believe that these direct observations of a low-frequency wave input must provoke a re-evaluation of solar wind acceleration by high frequency (kHz) ion-cyclotron modes. Title: Alfvén Waves in the Solar Corona Authors: Tomczyk, S.; McIntosh, S. W.; Keil, S. L.; Judge, P. G.; Schad, T.; Seeley, D. H.; Edmondson, J. Bibcode: 2007Sci...317.1192T Altcode: Alfvén waves, transverse incompressible magnetic oscillations, have been proposed as a possible mechanism to heat the Sun’s corona to millions of degrees by transporting convective energy from the photosphere into the diffuse corona. We report the detection of Alfvén waves in intensity, line-of-sight velocity, and linear polarization images of the solar corona taken using the FeXIII 1074.7-nanometer coronal emission line with the Coronal Multi-Channel Polarimeter (CoMP) instrument at the National Solar Observatory, New Mexico. Ubiquitous upward propagating waves were seen, with phase speeds of 1 to 4 megameters per second and trajectories consistent with the direction of the magnetic field inferred from the linear polarization measurements. An estimate of the energy carried by the waves that we spatially resolved indicates that they are too weak to heat the solar corona; however, unresolved Alfvén waves may carry sufficient energy. Title: Coronal Seismology: The Search for Propagating Waves in Coronal Loops Authors: Schad, Thomas A.; Seeley, D.; Keil, S. L.; Tomczyk, S. Bibcode: 2007AAS...210.9113S Altcode: 2007BAAS...39Q.206S We report on Doppler observations of the solar corona obtained in the Fe XeXIII 1074.7nm coronal emission line with the HAO Coronal Multi-Channel Polarimeter (CoMP) mounted on the NSO Coronal One Shot coronagraph located in the Hilltop Facility of NSO/Sacramento Peak. The COMP is a tunable filtergraph instrument that records the entire corona from the edge of the occulting disk at approximately 1.03 Rsun out to 1.4 Rsun with a spatial resolution of about 4” x 4”. COMP can be rapidly scanned through the spectral line while recording orthogonal states of linear and circular polarization. The two dimensional spatial resolution allows us to correlate temporal fluctuations observed in one part of the corona with those seen at other locations, in particular along coronal loops. Using cross spectral analysis we find that the observations reveal upward propagating waves that are characterized by Doppler shifts with rms velocities of 0.3 km/s, peak wave power in the 3-5 mHz frequency range, and phase speeds 1-3 Mm/s. The wave trajectories are consistent with the direction of the magnetic field inferred from the linear polarization measurements. We discuss the phase and coherence of these waves as a function of height in the corona and relate our findings to previous observations. The observed waves appear to be Alfvenic in character.

"Thomas Schad was supported through the National Solar Observatory Research Experiences for Undergraduate (REU) site program, which is co-funded by the Department of Defense in partnership with the National Science Foundation REU Program." Daniel Seeley was supported through the National Solar Observatory Research Experience for Teachers (RET) site program, which is funded by the National Science Foundation RET program. Title: COSMO: The Coronal Solar Magnetism Observatory Authors: Burkepile, Joan; Tomczyk, S.; Lin, H.; Zurbuchen, T.; Casini, R. Bibcode: 2007AAS...210.2519B Altcode: 2007BAAS...39..134B The COronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed to study coronal magnetic fields and their environment using the polarization of forbidden emission lines in the infrared. Supporting instruments focus on prominence and chromospheric magnetometry and imaging and the evolution of the electron scattered corona (K-corona). COSMO will address one of the least understood problems in Sun-Earth connections: the coronal magnetic field using breakthrough techonologies that have been successfully demonstrated with proof-of-concept instrumentation. We will present information about COSMO and science results from the prototype instruments, including the detection of Alfven waves in the corona. Title: Magnetic Field Vector Retrieval With the Helioseismic and Magnetic Imager Authors: Borrero, J. M.; Tomczyk, S.; Norton, A.; Darnell, T.; Schou, J.; Scherrer, P.; Bush, R.; Liu, Y. Bibcode: 2007SoPh..240..177B Altcode: 2006astro.ph.11565B We investigate the accuracy to which we can retrieve the solar photospheric magnetic field vector using the Helioseismic and Magnetic Imager (HMI) that will fly onboard of the Solar Dynamics Observatory by inverting simulated HMI profiles. The simulated profiles realistically take into account the effects of the photon noise, limited spectral resolution, instrumental polarization modulation, solar p modes, and temporal averaging. The accuracy of the determination of the magnetic field vector is studied by considering the different operational modes of the instrument. Title: Spectral Line Selection for HMI Authors: Norton, A. A.; Pietarila Graham, J. D.; Ulrich, R. K.; Schou, J.; Tomczyk, S.; Liu, Y.; Lites, B. W.; López Ariste, A.; Bush, R. I.; Socas-Navarro, H.; Scherrer, P. H. Bibcode: 2006ASPC..358..193N Altcode: We present information on two spectral lines, Fe I 6173 Å and Ni I 6768 Å, that were candidates for use in the Helioseismic and Magnetic Imager (HMI) instrument. Both Fe I and Ni I profiles have clean continuum and no blends that threaten performance. The higher Landé factor of Fe I means its operational velocity range in regions of strong magnetic field is smaller than for Ne I. Fe I performs better than Ni I for vector magnetic field retrieval. Inversion results show that Fe I consistently determines field strength and flux more accurately than the Ni I line. Inversions show inclination and azimuthal errors are recovered to ≈2° above 600 Mx/cm2 for Fe I and above 1000 Mx/cm2 for Ni I. The Fe I line was recommended, and ultimately chosen, for use in HMI. Title: Quiet-Sun Magnetism Seen with a Mn Line: Km-Sized Magnetic Structures Authors: López Ariste, A.; Ramírez Vélez, J. C.; Tomczyk, S.; Casini, R.; Semel, M. Bibcode: 2006ASPC..358...54L Altcode: We observed Manganese lines with large hyperfine structure and used them to disentangle strength from flux in the measurement of photospheric magnetic fields. In observations of the quiet sun with both ASP and THEMIS, we measure flux from the amplitude of Stokes V in Fe lines, and the Mn line, crudely analyzed, places the field strength either above or below a threshold of 600 G, which is set by the atomic structure. In the case of THEMIS observations, having determined magnetic flux and field strength for every pixel, one can estimate filling factors of the magnetic field and determine characteristic scales. Structures at scales smaller than 50 km are revealed. Title: Magnetic Field Vector Retrieval with HMI Authors: Borrero, J. M.; Tomczyk, S.; Norton, A. A.; Darnell, T.; Schou, J.; Scherrer, P.; Bush, R. I.; Lui, Y. Bibcode: 2006ASPC..358..144B Altcode: The Helioseismic and Magnetic Imager (HMI), on board the Solar Dynamics Observatory (SDO), will begin data acquisition in 2008. It will provide the first full-disk, high temporal cadence observations of the full Stokes vector with a 0.5 arcsec pixel size. This will allow for a continuous monitoring of the Solar magnetic-field vector. HMI data will advance our understanding of the small- and large-scale magnetic field evolution, its relation to the solar and global dynamic processes, coronal field extrapolations, flux emergence, magnetic helicity, and the nature of the polar magnetic fields. We summarize HMI's expected operation modes, focusing on the polarization cross-talk induced by the solar oscillations, and how this affects the magnetic-field vector determination. Title: Spectral Line Selection for HMI: A Comparison of Fe I 6173 Å and Ni I 6768 Å Authors: Norton, A. A.; Graham, J. Pietarila; Ulrich, R. K.; Schou, J.; Tomczyk, S.; Liu, Y.; Lites, B. W.; Ariste, A. López; Bush, R. I.; Socas-Navarro, H.; Scherrer, P. H. Bibcode: 2006SoPh..239...69N Altcode: 2006SoPh..tmp...88N; 2006astro.ph..8124N We present a study of two spectral lines, Fe I 6173 Å and Ni I 6768 Å, that were candidates to be used in the Helioseismic and Magnetic Imager (HMI) for observing Doppler velocity and the vector magnetic field. The line profiles were studied using the Mt. Wilson Observatory, the Advanced Stokes Polarimeter and the Kitt Peak-McMath Pierce telescope and one-meter Fourier transform spectrometer atlas. Both Fe I and Ni I profiles have clean continua and no blends that threaten instrument performance. The Fe I line is 2% deeper, 15% narrower, and has a 6% smaller equivalent width than the Ni I line. The potential of each spectral line to recover pre-assigned solar conditions is tested using a least-squares minimization technique to fit Milne-Eddington models to tens of thousands of line profiles that have been sampled at five spectral positions across the line. Overall, the Fe I line has a better performance than the Ni I line for vector-magnetic-field retrieval. Specifically, the Fe I line is able to determine field strength, longitudinal and transverse flux four times more accurately than the Ni I line in active regions. Inclination and azimuthal angles can be recovered to ≈2° above 600 Mx cm−2 for Fe I and above 1000 Mx cm−2 for Ni I. Therefore, the Fe I line better determines the magnetic-field orientation in plage, whereas both lines provide good orientation determination in penumbrae and umbrae. We selected the Fe I spectral line for use in HMI due to its better performance for magnetic diagnostics while not sacrificing velocity information. The one exception to the better performance of the Fe I line arises when high field strengths combine with high velocities to move the spectral line beyond the effective sampling range. The higher geff of Fe I means that its useful range of velocity values in regions of strong magnetic field is smaller than Ni I. Title: The Coronal Solar Magnetic Observatory (COSMO) Authors: Tomczyk, S.; Zurbuchen, T.; Kuhn, J.; Lin, H.; Judge, P.; Burkepile, J.; Casini, R. Bibcode: 2006AGUFMSM12A..03T Altcode: Measurement of magnetic fields in the corona is arguably the most important observable required for advances in our understanding of the emergence of magnetic flux into the solar atmosphere and the processes responsible for the production of solar activity, coronal heating and coronal dynamics. We discuss plans for the COronal Solar Magnetic Observatory (COSMO), which is a proposed ground-based suite of instruments designed to routinely study coronal magnetic fields and their environment. The core of the facility includes a meter-class coronagraph with instrumentation dedicated to measuring the coronal magnetic field using the polarization of forbidden emission lines in the infrared. Supporting instruments focus on prominence magnetometry and the dynamics of the electron-scattered corona (K-corona) and chromosphere. In addition to acquiring routine synoptic observations of coronal magnetic fields, the COSMO project will include the establishment of a community-based user advisory panel to accept observational campaigns submitted by members of the scientific community at-large. COSMO will enhance the value of existing and new observatories on the ground (SOLIS, ATST, FASR) and in space (SOHO, TRACE, GOES, Solar-B, STEREO and SDO) by providing unique and crucial observations of the global coronal magnetic field and its evolution and dynamics. Title: Quiet sun magnetic field diagnostics with a Mn line Authors: López Ariste, A.; Tomczyk, S.; Casini, R. Bibcode: 2006A&A...454..663L Altcode: Context: .The Mn line at 553 nm shows strong spectral features in both intensity and polarization profiles due to the hyperfine structure of the atom. These features, their presence or absence, are known to be dependent on the magnetic regime to which the Mn atom is subject.
Aims: .Our objective is to disentangle strong kilo-Gauss (kG) fields from relatively weak hecto-Gauss (hG) fields in the quiet sun, and compute relative filling factors on the resolution element.
Methods: .We observed the 553 nm Mn line in a quiet sun area with the Advanced Stokes Polarimeter, and we introduce an in-line ratio between different spectral features. Filling factors can be retrieved from the measurement of this ratio and the total longitudinal flux.
Results: .In the photospheric network the kG dominate the magnetic flux, although out of the higher concentration areas the hG fields dominate in surface coverage. For the internetwork (granules and lanes confounded) the hG are dominant both in surface and total flux.
Title: High Resolution Spectropolarimetry of Penumbral Formation with IBIS Authors: Reardon, Kevin; Casini, R.; Cavallini, F.; Tomczyk, S.; Rouppe van der Voort, L.; Van Noort, M.; Woeger, F.; Socas Navarro, H.; IBIS Team Bibcode: 2006SPD....37.3503R Altcode: 2006BAAS...38..260R We present the results of first spectropolarimetric observations made with the Interferometric Bidimensional Spectrometer (IBIS) at the NSO/Dunn Solar Telescope. The use of narrowband imaging and post-facto reconstruction techniques allows for observations close to the diffraction limit of the vector magnetic field. We will show observations of the the formation of an individual penumbral filament around a small pore. We measure the magnetic field and velocity field of the forming penumbral filament. The spectropolarimetric mode of IBIS will be available to the community in the fall of 2006. Title: Spinor: Visible and Infrared Spectro-Polarimetry at the National Solar Observatory Authors: Socas-Navarro, Hector; Elmore, David; Pietarila, Anna; Darnell, Anthony; Lites, Bruce W.; Tomczyk, Steven; Hegwer, Steven Bibcode: 2006SoPh..235...55S Altcode: 2005astro.ph..8685S The Spectro-Polarimeter for Infrared and Optical Regions (SPINOR) is a new spectro-polarimeter that will serve as a facility instrument for the Dunn Solar Telescope at the National Solar Observatory. This instrument is capable of achromatic polarimetry over a very broad range of wavelengths, from 430 to 1600 nm, allowing for the simultaneous observation of several visible and infrared spectral regions with full Stokes polarimetry. Another key feature of the design is its flexibility to observe virtually any combination of spectral lines, limited only by practical considerations (e.g., the number of detectors available, space on the optical bench, etc.). Title: Mauna Loa Solar Observatory and the SSSC Great Observatory Authors: Burkepile, J.; Darnell, T.; Tomczyk, S. Bibcode: 2005AGUFMSH51C1220B Altcode: Solar observations of the low corona, He I 1083.0 nm and H-alpha obtained at the Mauna Loa Solar Observatory (MLSO) provide an extensive complimentary and supporting dataset to many NASA missions such as STEREO, SDO, TRACE and Solar-B. These datasets, coupled with the Coronal Multichannel Polarimeter (CoMP), due to begin taking synoptic magnetic field measurements in the low corona in 2006, can provide valuable scientific contributions and extensions to many NASA programs. The Advanced Coronal Observing System (ACOS) at MLSO is comprised of three instruments: PICS, CHIP and Mk4, which together record the solar chromosphere and low corona every three minutes over a 9 hour observing day for an average of 340 days per year. The Coronal Multichannel Polarimeter (CoMP), images the low corona at 1074.7 and 1079.8 nm and the off limb chromosphere at 1083.0 nm. From these images, the line-of-sight (LOS) magnetic field strength and plane of sky direction are inferred from Stokes parameters. CoMP data were taken throughout the Summer of 2005 at the Sacramento Peak Observatory in Sunspot NM and plans are underway to start continuous synoptic observations there in 2006. Here we present highlights of the MLSO and CoMP datasets, emphasize recent work using NASA and MLSO datasets and discuss plans to provide new data products that compliment NASA data as well as combine NASA, MLSO and CoMP observations. Title: Full Stokes Spectropolarimetry of Hα in Prominences Authors: López Ariste, A.; Casini, R.; Paletou, F.; Tomczyk, S.; Lites, B. W.; Semel, M.; Landi Degl'Innocenti, E.; Trujillo Bueno, J.; Balasubramaniam, K. S. Bibcode: 2005ApJ...621L.145L Altcode: We report on spectropolarimetric observations of Hα in prominences made with the Télescope Héliographique pour l'Etude du Magnétisme et des Instabilités Solaires and the High Altitude Observatory/Advanced Stokes Polarimeter. Stokes Q and U show the expected profile shape from resonance scattering polarization and the Hanle effect. In contrast, most of the time, Stokes V does not show the antisymmetric profile shape typical of the Zeeman effect but a profile that indicates the presence of strong atomic orientation in the hydrogen levels, to an extent that cannot be explained by invoking the alignment-to-orientation transfer mechanism induced by the prominence magnetic field. We found that the largest signal amplitudes of Stokes V (comparable to that of Stokes Q and U) could be produced by a process of selective absorption of circularly polarized radiation from the photosphere, which requires that the prominence be in the vicinity of an active region. Although recent observations of active region filaments indicate such a selective absorption mechanism as a plausible explanation of the anomalous signals observed, the particular set of conditions that must be met suggest that a different explanation may be required to explain the almost ubiquitous symmetric V signal observed in Hα prominences. Therefore, we speculate that an alternative mechanism inducing strong atomic orientation at the observed level could be due to the presence of electric fields inducing an electric Hanle effect on Hα. Although we are still working toward a careful modeling of this effect, including both electric and magnetic fields, we present some preliminary considerations that seem to support this possibility. Title: Magnetic Field Measurements from The Coronal Multi-Channel Polarimeter Authors: Tomczyk, S. Bibcode: 2004AGUFMSH31B..04T Altcode: We have constrcted a filter-based polarimeter optimized for the measurement of magnetic fileds in the solar corona. The instrument will observe the coronal emission lines of FeXIII at 1074.7 and 1079.8 nm as well as the chromospheric HeI emission line at 1083 nm. The instrument consists of a polarimeter allowing complete Stokes I,Q,U,V measurement followed by a Lyot birefringent filter with dual passbands of 0.14 nm width. Both the polarimeter and filter employ liquid crystals for rapid electro-optical tuning. Measurement of the longitudinal Zeeman effect provides information on the strength of the line-of-sight component of the magnetic field while the observation of resonance scattering will constrain the plane-of-sky field direction. Precise measurement of plasma velocity is also possible. Such measurements are critical for addressing many outstanding problems in coronal physics. This instrument was deployed to the 20-cm One Shot coronagraph at NSO's Sacramento Peak Observatory in January of 2004. Observations were obtained during observing runs in March, May and August of 2004. Results from these observing runs will be presented. Title: Background-Induced Measurement Errors of the Coronal Intensity, Density, Velocity, and Magnetic Field Authors: Penn, M. J.; Lin, H.; Tomczyk, S.; Elmore, D.; Judge, P. Bibcode: 2004SoPh..222...61P Altcode: The effect of a background signal on the signal-to-noise ratio is discussed, with particular application to ground-based observations of emission lines in the solar corona with the proposed Advanced Technology Solar Telescope. The concepts of effective coronal aperture and effective coronal integration time are introduced. Specific expressions are developed for the 1σ measurement errors for coronal intensity, coronal electron density, coronal velocity, and coronal magnetic field measurements using emission lines and including a background. Title: Initial Magnetic Field Measurements from The Coronal Multi-Channel Polarimeter Authors: Tomczyk, S.; Card, G. L.; Darnell, T.; Elmore, D. F.; Casini, R.; Judge, P. G.; Burkepile, J. Bibcode: 2004AAS...204.2002T Altcode: 2004BAAS...36..686T We have constrcted a filter-based polarimeter optimized for the measurement of magnetic fileds in the solar corona. The instrument will observe the coronal emission lines of FeXIII at 1074.7 and 1079.8 nm as well as the chromospheric HeI emission line at 1083 nm. The instrument consists of a polarimeter allowing complete Stokes I,Q,U,V measurement followed by a Lyot birefringent filter with dual passbands of 0.14 nm width. Both the polarimeter and filter employ liquid crystals for rapid electro-optical tuning. This instrument was deployed to the 20-cm One Shot coronagraph at NSO's Sacramento Peak Observatory in January of 2004.

Measurement of the longitudinal Zeeman effect provides information on the strength of the line-of-sight component of the magnetic field while the observation of resonance scattering will constrain the plane-of-sky field direction. Precise measurement of plasma velocity is also possible. Such measurements are critical for addressing many outstanding problems in coronal physics.

The operation and performance of the instrument will be described. We will also describe the methodology for the coronal magnetic field measurement. Initial measurements taken with the instrument will be presented. This research was supported by the NSF. Title: Multi-Channel Polarimeter for Coronal Magnetic Filed Measurements Authors: Tomczyk, S. Bibcode: 2003AGUFMSH42D..03T Altcode: We are currently building a filter-based polarimeter optimized for the measurement of magnetic fileds in the solar corona through observations of the coronal emission lines of Fe XIII at 1074.7 and 1079.8 nm. The instrument consists of a polarimeter allowing complete Stokes I,Q,U,V measurement followed by a Lyot birefringent filter with dual passbands of 0.14 nm width. Both the polarimeter and filter employ liquid crystals for rapid electro-optical tuning. This instrument will be deployed at the One Shot coronagraph at NSO Sac Peak. Measurement of the longitudinal Zeeman effect will yield information on the strength of the line-of-sight component of the magnetic field while the observation of resonance scattering will constrain the plane-of-sky field direction. Precise measurement of plasma velocity will also be possible. Such measurements are critical for addressing many outstanding problems in coronal physics. The operation and performance of the instrument will be described. We will also describe the methodology for the coronal magnetic field measurement. Preliminary measurements with the instrument at the One Shot coronagraph will be presented. Title: A Coronal Multi Channel Polarimeter For Magnetic Field Measurements Authors: Darnell, T.; Tomczyk, S.; Card, G.; Judge, P. G.; Casini, R.; Burkepile, J. Bibcode: 2003AGUFMSH42B0505D Altcode: The Coronal Multi-channel Polarimeter (CoMP) is a filter-based polarimeter designed to provide quantitative measurements of magnetic fields in the solar corona. It will measure the Stokes parameters at the 1074.7 and 1079.8 FeXIII coronal emission lines (1.67 x 106 degrees K), and the 1083.0 nm HeI chromospheric line. The CoMP is based on a four stage birefringent filter and is designed such that the corona is imaged in two wavelengths simultaneously. The strength of the line-of-sight component of the coronal magnetic field is inferred from the measured amplitude of the Stokes V profile and an estimate of the plane-of-sky direction is made from the Stokes U/Q ratio. Further, inference of line-of-sight velocities can be made from Stokes I (red and blue wing) amplitudes. Finally, it may be possible to obtain a coronal density diagnostic capability from the ratio of the 1074.7/1079.8 amplitudes. This poster will present the latest test results as well as any preliminary data that have been obtained. Title: Magnetic maps of prominences Authors: Casini, R.; Lopez Ariste, A.; Tomczyk, S.; Lites, B. Bibcode: 2003AGUFMSH42D..05C Altcode: We present the first magnetic maps of a prominence obtained by applying our PCA inversion approach to prominence spectropolarimetric data in the He I D3 line. Our results indicate the presence of organized structures in the prominence plasma embedded in magnetic field that are significantly larger than average (50 G and higher). We reaffirm the need for a Hanle-based diagnostics of prominence magnetism using full Stokes spectropolarimetry, and the importance of improved, multi-line observations, ideally involving both He I D3 and 10830. Title: Magnetic Maps of Prominences from Full Stokes Analysis of the He I D3 Line Authors: Casini, R.; López Ariste, A.; Tomczyk, S.; Lites, B. W. Bibcode: 2003ApJ...598L..67C Altcode: We present the first magnetic maps of a prominence, derived from inversion of spectropolarimetric data in He I D3 using the principal component analysis of all four Stokes profiles. This prominence, along with several others, was observed in 2002 May using the Dunn Solar Telescope of the National Solar Observatory/Sacramento Peak Observatory, equipped with the High Altitude Observatory Advanced Stokes Polarimeter. The use of an unocculted instrument allowed us to map the prominence magnetic fields down to the chromospheric limb. Our analysis indicates that the average magnetic field in prominences is mostly horizontal and varies between 10 and 20 G, thus confirming previous findings. However, our maps show that fields significantly stronger than average, even as large as 60 or 70 G, can often be found in clearly organized plasma structures of the prominence. Title: Study of p-mode excitation and damping rate variations from IRIS++ observations Authors: Salabert, D.; Jiménez-Reyes, S. J.; Tomczyk, S. Bibcode: 2003A&A...408..729S Altcode: 11 years of low degree helioseismic data collected by the IRIS++ network (International Research of the Interior of the Sun) have been analyzed. The epoch covered (mid-1989 to end-1999) spans the maximum and the falling phase of solar cycle 22 and the rising phase of the current solar cycle 23. Annual timeseries with an overlap of 6 months are used to study the variations with solar activity of the p-mode frequencies nu n,l, heights Hn,l, and linewidths Gamma n,l, taking into account the effects of the window function. These are used to infer variations in the velocity power <Vn,l2> and the energy supply rate dot En,l which relate to changes in the excitation and the damping of the modes. We find global changes over the range 2600 <= nu <= 3600 mu Hz of about -26%, 11%, -11% for the heights, the linewidths, and the velocity power respectively, and a constant energy supply to the modes. Title: Eleven years of IRIS frequencies and splittings Authors: Fossat, E.; Salabert, David; Cacciani, A.; Ehgamberdiev, S.; Gelly, B.; Grec, G.; Hoeksema, J. T.; Kholikov, S.; Lazrek, M.; Palle, P.; Schmider, F. X.; Tomczyk, S. Bibcode: 2003ESASP.517..139F Altcode: 2003soho...12..139F Having acquired since July, 1989, a complete 11-year solar cycle of full disk data, the IRIS++ network has now made available to anyone the longest helioseismic data base to-date. A few results obtained from this very long time series are briefly presented here, with some emphasis on the low degree p-mode frequencies themselves, and their rotational splittings that have been estimated with unprecedented accuracy. Title: A first study of the excitation and damping rate variations extracted from IRIS++ observations Authors: Salabert, D.; Jiménez-Reyes, S. J.; Tomczyk, S. Bibcode: 2003ESASP.517..377S Altcode: 2003soho...12..377S The IRIS++ network (International Research of the Interior of the Sun) have collected 11 years of low-l helioseismic data. Annual time series with an overlapping of 6 months are used to study the variations over the solar activity cycle of the different p-mode parameters. We find a global change of about -26% in the amplitudes, 14% in the linewidth and -12% in the velocity power while the rate at which the energy is supplied remains constant. Title: Polarimeter for the study of magnetic fields in prominences Authors: Lopez Ariste, Arturo; Tomczyk, Steven; Semel, Meir; Darnell, A. Bibcode: 2003SPIE.4853..235L Altcode: We report on a new spectropolarimeter for the measurement of vector magnetic fields on prominences using the HeD3 line in the Evans Solar Facility at the Sacramento Peak Observatory. Title: Hyperfine Structure as a Diagnostic Tool of Solar Magnetic Fields Authors: López Ariste, A.; Tomczyk, S.; Casini, R. Bibcode: 2003ASPC..307..115L Altcode: No abstract at ADS Title: The Helioseismic and Magnetic Imager (HMI) on SDO: Full Vector Magnetography with a Filtergraph Polarimeter Authors: Graham, J. D.; Norton, A.; López Ariste, A.; Lites, B.; Socas-Navarro, H.; Tomczyk, S. Bibcode: 2003ASPC..307..131G Altcode: No abstract at ADS Title: Vector Magnetic Field Measurement Capabiliity of the Helioseismic and Magnetic Imager on SDO Authors: Bush, R.; Scherrer, P.; Schou, J.; Liu, Y.; Tomczyk, S.; Graham, J.; Norton, A. Bibcode: 2002AGUFMSH52A0464B Altcode: The Helioseismic and Magnetic Imager (HMI) instrument has been selected as part of the payload complement of the Solar Dynamics Observatory Spacecraft. In this poster we describe the observing technique for measuring solar vector magnetic fields. The expected performance of the HMI instrument will be discussed including results of modeling the observing lines and instrument. Title: Hyperfine Structure as a Diagnostic of Solar Magnetic Fields Authors: López Ariste, A.; Tomczyk, S.; Casini, R. Bibcode: 2002ApJ...580..519L Altcode: We propose the use of the Zeeman effect of the hyperfine structure (HFS) as a diagnostic of solar photospheric magnetic fields. The HFS induces unique signatures in the polarized spectra of particular atoms, which can be used to directly get information on the magnetic field strength. To explore the effects of HFS, we adopt a numerical model of line formation and radiative transfer of polarized light in a magnetized Milne-Eddington atmosphere. We concentrate our studies on several lines of Mn I, which show particularly striking HFS signatures in the solar atlas. For these lines, anomalous Stokes profiles are produced for fields in the range 0-1000 G. The presence of these unusual profiles for weak magnetic fields constitutes a novel and potentially powerful diagnostic of the strength of solar magnetic fields in the quiet photosphere and plages. Title: Spectroscopic Detection of the 3.934 Micron Line of Si IX in the Solar Corona Authors: Judge, P. G.; Tomczyk, S.; Livingston, W. C.; Keller, C. U.; Penn, M. J. Bibcode: 2002ApJ...576L.157J Altcode: We report the detection of the 2s22p23P1-->0 line of Si IX using the McMath-Pierce telescope on Kitt Peak. Observations were made of the solar disk and at various heights above the limb between 2002 May 13 and 17, under nonideal sky conditions, using the 13.5 m vertical spectrograph and an InSb single-diode detector. We report a new rest wavelength for the line and discuss its potential use as a diagnostic of coronal magnetic fields using ground-based telescopes. Our observations give λrest=3.93434+/-0.00007 μm, consistent with earlier less accurate values, but it places the blue wing of the line under a strong telluric N2O line. In the active regions observed, the line's intensity is comparable to or larger than predicted in earlier work for the quiet Sun. Title: Inference of Solar Magnetic Field Parameters from Data with Limited Wavelength Sampling Authors: Graham, Jonathan D.; López Ariste, Arturo; Socas-Navarro, Hector; Tomczyk, Steven Bibcode: 2002SoPh..208..211G Altcode: We investigate the diagnostic potential of polarimetric measurements with filtergraph instruments. Numerical simulations are used to explore the possibility of inferring the magnetic field vector, its filling factor, and the thermodynamics of model atmospheres when only a few wavelength measurements are available. These simulations assume the magnetic Sun to be represented by Milne-Eddington atmospheres. The results indicate that two wavelength measurements are insufficient to reliably determine the magnetic parameters, regardless of whether magnetograph techniques or least-squares fitting inversions are used. However, as few as four measurements analyzed with the inversion technique provide enough information to retrieve the intrinsic magnetic field with an accuracy better than 10% in most cases. Title: IRIS++ database: Merging of IRIS + Mark-1 + LOWL Authors: Salabert, D.; Fossat, E.; Gelly, B.; Tomczyk, S.; Pallé, P.; Jiménez-Reyes, S. J.; Cacciani, A.; Corbard, T.; Ehgamberdiev, S.; Grec, G.; Hoeksema, J. T.; Kholikov, S.; Lazrek, M.; Schmider, F. X. Bibcode: 2002A&A...390..717S Altcode: The IRIS network has been operated continuously since July 1st 1989. To date, it has acquired more than a complete solar cycle of full-disk helioseismic data which has been used to constrain the structure and rotation of the deep solar interior. However, the duty cycle of the network data has never reached initial expectations. To improve this situation, several cooperations have been developed with teams collecting observations with similar instruments. This paper demonstrates that we are able to merge data from these different instruments in a consistent manner resulting in a very significant improvement in network duty cycle over more than one solar cycle initiating what we call the IRIS++ network. The integrated radial velocities from the IRIS++ database (1989 to 1999) are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/390/717 Title: Inference of Solar Vector Magnetic Fields with Filtergraph Instruments Authors: Graham, J. D.; Lites, B. W.; López Ariste, A.; Norton, A.; Socas-Navarro, H.; Tomczyk, S. Bibcode: 2002AAS...200.5611G Altcode: 2002BAAS...34..736G We investigate the diagnostic potential of polarimetric measurements with filtergraph instruments. Numerical simulations are used to explore the possibility of inferring the magnetic field vector, its filling factor, and the thermodynamics of model atmospheres when only a few wavelength measurements are available. The simulations assume the magnetic sun to be represented by Milne-Eddington (ME) atmospheres. The results indicate that two wavelength measurements are insufficient to reliably determine the magnetic parameters, regardless of whether magnetograph techniques or least-squares fitting inversions are used. However, as few as four measurements analyzed with the inversion technique provide enough information to retrieve the intrinsic magnetic field with an accuracy better than 10 generated by more general models and ASP data passed through a simulated filtergraph. Title: New Polarization Diagnostics for the Solar Atmosphere Authors: Casini, R.; López Ariste, A.; Tomczyk, S.; Lites, B. Bibcode: 2002AAS...200.3403C Altcode: 2002BAAS...34..690C We present relatively new diagnostics of ``weak" magnetic fields in the solar atmosphere. The first diagnostic is suggested by recent advances in the inversion of Stokes profiles of lines formed by resonance scattering in the weakly magnetized plasma of prominences (Hanle effect and level-crossing; 0 to 100 G). Use of pattern recognition techniques (PCA) in this field has marked a sensible progress with respect to previous diagnostic procedures. The second diagnostic is the modelling of hyperfine structured (HFS) lines that can be observed in the spectrum of the quiet photosphere. This allows to investigate relatively weak photospheric fields (200 G to 1000 G), in which regime the HFS induces peculiar signatures in the Stokes profiles, including the appearance of subcomponents and net circular polarization. The third diagnostic is suggested by interesting polarization properties of the Na I D1 line formed by resonance scattering: the atomic polarization in the upper level of D1, which is responsible of a characteristic antisymmetric (i.e., V-like) signature in the core of Stokes Q, is rapidly suppressed for B > 10 G, irrespective of the magnetic field direction. A common denominator of these three diagnostics is their sensitivity to the actual strength of the magnetic field, instead of the magnetic flux within the resolution element. Another common aspect is that all require (or would profit from) high polarization sensitivity, which will be one of the strengths of ATST. For the diagnostics of prominence magnetic fields, the possibility of multiline spectropolarimetry could be decisive. Simultaneous observations of He I D3 (5876A) and 10830A, or of He I D3 and the Na I D lines (all within a 20A spectral range!), would increase the inversion accuracy of PCA. The high spatial resolution capabilities of ATST would be advantageous mostly to diagnose weak photospheric fields, already at the present time. Because of the complexity of radiative transfer in complicated structures like prominences, high spatial resolution in these structures is not the highest priority. However, we hope that when ATST will become operative, this complicated problem will have been attacked succesfully. Title: Analysis of variability of p-mode parameters in 11 years of IRIS data Authors: Salabert, D.; Jiménez-Reyes, S. J.; Fossat, E.; Cacciani, A.; Ehgamberdiev, S.; Gelly, B.; Grec, G.; Hoeksema, J. T.; Khalikov, S.; Lazrek, M.; Pallé, P.; Schmider, F. X.; Tomczyk, S. Bibcode: 2002ESASP.477..253S Altcode: 2002scsw.conf..253S 11 years of IRIS (the low degree helioseismology network) have been analysed for the study of p-modes parameters variability. The duty cycle of the network data has been improved by the partial gap filling method named "repetitive music". This paper discusses the variations of all p-modes parameters along these 11 years. Title: Analysis of the solar cycle and core rotation using 15 years of Mark-I observations: 1984-1999 . I. The solar cycle Authors: Jiménez-Reyes, S. J.; Corbard, T.; Pallé, P. L.; Roca Cortés, T.; Tomczyk, S. Bibcode: 2001A&A...379..622J Altcode: 2001astro.ph.10364J High quality observations of the low-degree acoustic modes (p-modes) exist for almost two complete solar cycles using the solar spectrophotometer Mark-I, located at the Observatorio del Teide (Tenerife, Spain) and operating now as part of the Birmingham Solar Oscillations Network (BiSON). We have performed a Fourier analysis of 30 calibrated time-series of one year duration covering a total period of 15 years between 1984 and 1999. Applying different techniques to the resulting power spectra, we study the signature of the solar activity changes on the low-degree p-modes. We show that the variation of the central frequencies and the total velocity power (TVP) changes. A new method of simultaneous fit is developed and a special effort has been made to study the frequency-dependence of the frequency shift. The results confirm a variation of the central frequencies of acoustic modes of about 0.45 mu Hz, peak-to-peak, on average for low degree modes between 2.5 and 3.7 mHz. The TVP is anti-correlated with the common activity indices with a decrease of about 20% between the minimum and the maximum of solar cycle 22. The results are compared with those obtained for intermediate degrees, using the LOWL data. The frequency shift is found to increase with the degree with a weak l-dependence similar to that of the inverse mode mass. This verifies earlier suggestions that near surface effects are predominant. Title: Variations of the solar interior with the cycle: observational aspects. Authors: Corbard, Thierry; Jimenez-Reyes, S. J.; Thompson, M. J.; Tomczyk, S. Bibcode: 2001sf2a.conf..109C Altcode: Helioseismic observations of long duration now open the possibility of studying the variation of the interior of the Sun during its cycle of activity. In particular, the possible dynamic or structure variations of the interface between the convective zone and the radiative interior, or tachocline, is of great interest to constrain solar dynamo models and to understand the phenomena at the origin of the cycle of activity observed at the surface. We have analysed the observations obtained during the 6 last years by the LOWL instrument located at Mauna Loa, Hawaii as well as the observations in integrated disc covering more than one solar cycle (1984-2000) by MARK-I instrument at the Peak del Teide, Tenerife. The results concerning the signature of the solar activity on the pressure modes of low and medium degrees and seeks for possible variations of the dynamic of the tachocline will be presented and replaced in the theoretical context. Title: Coronal Magnetometry: A Feasibility Study Authors: Judge, P. G.; Casini, R.; Tomczyk, S.; Edwards, D. P.; Francis, E. Bibcode: 2001STIN...0227999J Altcode: Measurements of components of the vector magnetic field in the solar corona can potentially yield information critical to our understanding of coronal structure, dynamics and heating. In this report we re-examine various techniques for such measurements, in particular those that can be applied outside of active regions, to investigate issues critical to the development of a new 'coronal magnetometer,' and to lay down some foundations upon which a suitable instrument may be developed for synoptic observations. The well-known forbidden coronal emission lines of magnetic dipole (M1) character appear to have the highest potential to address outstanding problems in coronal physics, especially those related to the storage and release of magnetic free energy. Measurements of the full Stokes vector of M1 lines can constrain both the line-of-sight (LOS) field strength, through the longitudinal Zeeman effect seen in Stokes V profiles, and the direction of the vector field projected onto the plane-of-the-sky (POS), through the analysis of resonance scattering-induced linear polarization seen in Stokes Q and U, in the so-called 'strong field' regime of the Hanl effect. Title: The solar tachocline and its variation (?) Authors: Corbard, T.; Jiménez-Reyes, S. J.; Tomczyk, S.; Dikpati, M.; Gilman, P. Bibcode: 2001ESASP.464..265C Altcode: 2001soho...10..265C; 2000astro.ph.11367C The solar tachocline, located at the interface between the latitude-dependent rotation of the convection zone and the rigid radiative interior, presents high gradients of angular velocity which are of particular interest for the models of the solar dynamo and angular momentum transport. Furthermore, latitudinal and temporal variations of the tachocline parameters, if any, are also of particular interest in order to constrain models. We present a review of some of the theories of the tachocline and their predictions that may be tested by helioseismology. We describe the methods for inferring the tachocline parameters from obervations and the associated difficulties. A review of results previously obtained is given and an analysis of the new 6 years database of LOWL observations is presented which yields no compelling evidence of variations or general trend of the tachocline parameters during the ascending phase of the current solar cycle (1994-2000). Title: Calibration procedure for the polarimetric instrument for Solar Eclipse-98 Authors: Elmore, David F.; Card, G. L.; Lecinski, A. R.; Lites, Bruce W.; Streander, Kim V.; Tomczyk, Steven Bibcode: 2000SPIE.4139..370E Altcode: We describe a ground-based eclipse instrument for measuring solar coronal polarization brightness and intensity, and the calibration procedures for this instrument. We present coronal measurements from the February 26, 1998 total solar eclipse observed at Curacao, N.A.. The instrument employs a liquid crystal variable retarder for analysis of coronal broad band linear polarization and collects data on an array detector spanning a 6.5 solar radius field of view. Polarization calibration of the liquid crystal variable retarder utilizes the tangential orientation of coronal polarization to calculate retardance values. Title: A New Precise Measurement of the Coronal Magnetic Field Strength Authors: Lin, Haosheng; Penn, Matthew J.; Tomczyk, Steven Bibcode: 2000ApJ...541L..83L Altcode: Magnetism dominates the structure and dynamics of the solar corona. Current theories suggest that it may also be responsible for coronal heating. Despite the importance of the magnetic field in the physics of the corona and despite the tremendous progress made recently in the remote sensing of solar magnetic fields, reliable measurements of the coronal magnetic field strength and orientation do not exist. This is largely due to the weakness of coronal magnetic fields, previously estimated to be on the order of 10 G, and the difficulty associated with observing the extremely faint solar corona emission. Using a very sensitive infrared spectropolarimeter to observe the strong near-infrared coronal emission line Fe XIII λ10747 above active regions, we have succeeded in measuring the weak Stokes V circular polarization profiles resulting from the longitudinal Zeeman effect of the magnetic field of the solar corona. From these measurements, we infer field strengths of 10 and 33 G from two active regions at heights of h=0.12 Rsolar and h=0.15 Rsolar, respectively. We expect that this measurement technique will allow, in the near future, the routine precise measurement of the coronal magnetic field strength with application to many critical problems in solar coronal physics. Title: Solar cycle variations of oscillation mode parameters from LOWL and MARK-I instruments Authors: Jimeńez Reyes, S. J.; Corbard, T.; Tomczyk, S.; Pallé, P. L. Bibcode: 2000SPD....31.0112J Altcode: 2000BAAS...32.1289J The signature of the Solar-Cycle appears clearly in the p-mode parameters (Jiménez-Reyes et al. 1998, Libbrecht & Woodard 1990, and Anguera et al. 1992). At present, the study of the p-mode parameter variation is a very active topic in helioseismology where, thanks to projects like BISON, IRIS, GONG, LOWL and MDI, we are able for the first time to analyse, using heliosismology, how the Sun internal structure and dynamic change over the magnetic cycle. High-quality observations for low degree p-modes have been accumulated for more than twenty years using the solar spectro photometer MARK-I, located and operating at the Observatorio del Teide (Tenerife, Spain). The data-base available have been re-analyzed over a much wider time interval than before. Moreover, the LOWL instrument, a Potassium Magneto-Optical Filter, located at the Manua Loa Observatory, has been measuring for more than six years solar oscillations of intermadiate p-mode degree. The data-base represents one of the best available to analyze the influence of the Solar-Cycle on the mode parameters, mainly because these data, concerning both low and intermadiate degree modes, give us information over an extensive range of the solar depths which may allow us to locate characteristics of the solar dynamo process. Using different data sets and different techniques, we analyse the behaviour of the solar p-modes in an attempt to better understand the origin of the Solar-Cycle. Title: The ECHO (Experiment for Coordinated Helioseismic Observations) Network Authors: Tomczyk, S.; Jiménez Reyes, S. J.; Jiménez, A.; Pallé, P. L. Bibcode: 2000SPD....31.0117T Altcode: 2000BAAS...32..804T The High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) in collaboration with the Instituto de Astrofísica de Canarias (IAC) have recently completed a two-station helioseismic network with sites at Mauna Loa, Hawaii and Izana, Tenerife. The instruments are Doppler imagers employing Magneto-Optical filters and are based on the existing LOWL instrument. We expect the network to provide a duty cycle of 50%, compared to 22% for the LOWL. In addition, the ECHO incorporates several improvements over the LOWL including: 1) a CCD detector with square pixels and a factor of two increase in spatial resolution; 2) better guiding; 3) exchange of red and blue images every 15 seconds to better facilitate detector flat fielding; and 4) improved thermal control of the instrument enclosure. We will present initial data from the network and demonstrate network performance. Title: Solar rotation From GOLF/LOWL Authors: Corbard, T.; Jiménez Reyes, S. J.; Tomczyk, S.; GOLF Team Bibcode: 2000SPD....31.0102C Altcode: 2000BAAS...32..801C The solar core rotation is an important open question that can be addressed by using observations from the spacecraft SOHO and ground based instruments. In particular, GOLF experiment on board SoHO is dedicated to the observation of low-degree oscillations which penetrate the solar core and it has been operating for more than three years. Similarly, LOWL instrument has been collecting data from ground for both low and intermediate degrees for more than 6 years. It is now well established that the differential rotation observed at the surface persists in the convection zone and become mainly solid in the radiative interior through a transition zone called the tachocline. Nevertheless it is still controversial to know if the core is rotationg slower, faster or at the same rate than the radiative interior. We use new data acquired during the last years and recently analysed from GOLF and LOWL in order to give an up to date status of our knowledge on the solar core rotation. Title: p-mode Frequency Shift as Solar Activity Index Authors: Jiménez-Reyes, S. J.; Corbard, Thierry; Palle, Pere L.; Tomczyk Bibcode: 2000ESASP.463..341J Altcode: 2000sctc.proc..341J No abstract at ADS Title: Dynamics of polar plumes observed at the 1998 February 26 eclipse Authors: Lites, B. W.; Card, G.; Elmore, D. F.; Holzer, T.; Lecinski, A.; Streander, K. V.; Tomczyk, S.; Gurman, J. B. Bibcode: 1999SoPh..190..185L Altcode: This paper presents first observations of dynamics of the white-light solar corona detected during the few minutes of totality of a solar eclipse. Perturbations of a polar plume associated with an embedded `jet' structure observed simultaneously at 195 Å with the EUV Imaging Telescope (EIT) aboard the SOHO spacecraft lead to estimates of the electron density fluctuations accompanying the jet: ±15%. The morphological behavior of the jet, its apparent upward propagation speed of ≈200 km s−1, and the inferred density perturbations suggest that the jet is led by a weak, outward-propagating shock resulting from the injection of material at high velocity at the base of the corona. Smaller perturbations of the white-light corona are apparent at many other locations, sustaining hope that propagating Alfvén waves may be measurable in the solar corona. Density perturbations associated with the jet follow from empirical electron density models of the polar inter-plume and plume regions, as derived from the ground-based eclipse measurements of coronal polarization brightness. These models indicate polar plume densities 4-6 times that of the interplume low corona. Title: Helioseismic Constraints on the Structure of the Solar Tachocline Authors: Charbonneau, P.; Christensen-Dalsgaard, J.; Henning, R.; Larsen, R. M.; Schou, J.; Thompson, M. J.; Tomczyk, S. Bibcode: 1999ApJ...527..445C Altcode: This paper presents a series of helioseismic inversions aimed at determining with the highest possible confidence and accuracy the structure of the rotational shear layer (the tachocline) located beneath the base of the solar convective envelope. We are particularly interested in identifying features of the inversions that are robust properties of the data, in the sense of not being overly influenced by the choice of analysis methods. Toward this aim we carry out two types of two-dimensional linear inversions, namely Regularized Least-Squares (RLS) and Subtractive Optimally Localized Averages (SOLA), the latter formulated in terms of either the rotation rate or its radial gradient. We also perform nonlinear parametric least-squares fits using a genetic algorithm-based forward modeling technique. The sensitivity of each method is thoroughly tested on synthetic data. The three methods are then used on the LOWL 2 yr frequency-splitting data set. The tachocline is found to have an equatorial thickness of w/Rsolar=0.039+/-0.013 and equatorial central radius rc/Rsolar=0.693+/-0.002. All three techniques also indicate that the tachocline is prolate, with a difference in central radius Δrc/Rsolar~=0.024+/-0.004 between latitude 60° and the equator. Assuming uncorrelated and normally distributed errors, a strictly spherical tachocline can be rejected at the 99% confidence level. No statistically significant variation in tachocline thickness with latitude is found. Implications of these results for hydrodynamical and magnetohydrodynamical models of the solar tachocline are discussed. Title: Rotation of the solar core from BiSON and LOWL frequency observations Authors: Chaplin, W. J.; Christensen-Dalsgaard, J.; Elsworth, Y.; Howe, R.; Isaak, G. R.; Larsen, R. M.; New, R.; Schou, J.; Thompson, M. J.; Tomczyk, S. Bibcode: 1999MNRAS.308..405C Altcode: Determination of the rotation of the solar core requires very accurate data on splittings for the low-degree modes which penetrate to the core, as well as for modes of higher degree to suppress the contributions from the rest of the Sun to the splittings of the low-degree modes. Here we combine low-degree data based on 32 months of observations with the BiSON network and data from the LOWL instrument. The data are analysed with a technique that specifically aims at obtaining an inference of rotation that is localized to the core. Our analysis provides what we believe is the most stringent constraint to date on the rotation of the deep solar interior. Title: The Rotation of the Solar Core Inferred by Genetic Forward Modeling Authors: Charbonneau, P.; Tomczyk, S.; Schou, J.; Thompson, M. J. Bibcode: 1998ApJ...496.1015C Altcode: Genetic forward modeling is a genetic algorithm-based modeling technique that can be used to perform helioseismic inversions of the Sun's internal angular velocity profile. The method can easily accommodate constraints such as positivity and monotonicity and readily lends itself to the use of robust statistical goodness-of-fit estimators. After briefly describing the technique, we ascertain its performance by carrying out a series of inversions for artificial splitting data generated from a set of synthetic internal rotation profiles characterized by various small inward increases in angular velocity in the deep solar core (r/R <= 0.5). These experiments indicate that the technique is accurate down to r/R ~= 0.2, and retains useful sensitivity down to r/R ~= 0.1.

We then use genetic forward modeling in conjunction with the LOW degree L (LOWL) 2 year frequency-splitting data set to determine the rotation rate in the deep solar core. We perform a large set of one-dimensional and 1.5-dimensional inversions using regularized least-squares minimization, conventional least-squares minimization with a monotonicity constraint (∂Ω/∂r <= 0), and inversions using robust statistical estimators. These calculations indicate that the solar core rotates very nearly rigidly down to r/R ~ 0.1. More specifically, on spatial scales >~0.04 R we can rule out inward increases by more than 50% down to r/R = 0.2, and by more than a factor of 2 down to r/R = 0.1. Thorough testing of various possible sources of bias associated with our technique indicates that these results are robust with respect to intrinsic modeling assumptions. Consequences of our results for models of the rotational evolution of the Sun and solar-type stars are discussed. Title: Solar internal sound speed as inferred from combined BiSON and LOWL oscillation frequencies Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Chaplin, W. J.; Elsworth, Y.; Isaak, G. R.; New, R.; Schou, J.; Thompson, M. J.; Tomczyk, S. Bibcode: 1997MNRAS.292..243B Altcode: 1997astro.ph..2105B Observations of the Sun with the LOWL instrument provide a homogeneous set of solar p-mode frequencies from low to intermediate degree that allow one to determine the structure of much of the solar interior avoiding systematic errors that are introduced when different data sets are combined, i.e., principally the effects of solar cycle changes on the frequencies. Unfortunately, the LOWL data set contains very few of the lowest-degree modes, which are essential for determining reliably the structure of the solar core - in addition, these lowest-degree data have fairly large associated uncertainties. However, observations made by the Birmingham Solar-Oscillations Network (BiSON) in integrated sunlight provide high-accuracy measurements of a large number of low-degree modes. In this paper we demonstrate that the low-degree mode set of the LOWL data can be successfully combined with the more accurate BiSON data, provided the observations are contemporaneous for those frequencies where the solar cycle induced effects are important. We show that this leads to a factor of 2 decrease in the error on the inferred sound speed in the solar core. We find that the solar sound speed is higher than in solar models for r<0.2Rsolar. The density of the solar core is, however, lower than that in solar models. Title: Solar internal rotation from LOWL data. A 2D regularized least-squares inversion using B-splines. Authors: Corbard, T.; Berthomieu, G.; Morel, P.; Provost, J.; Schou, J.; Tomczyk, S. Bibcode: 1997A&A...324..298C Altcode: Observations of surface oscillations of the Sun can be analyzed to probe the solar interior. We use data obtained by the LOWL instrument (LOWL is an abbreviation for low degree with degree denoted by L) installed on Mauna Loa, Hawaii, since 1994 to investigate solar internal rotation. A 2 Dimensional Regularized Least-Squares (2D RLS) inverse method based on an expansion of the solution on B-splines of arbitrary order is presented and applied to a 2 year dataset. This method insures the regularity of the solution in the center and introduces surface constraints. The choice of trade-off parameters in the regularization term is discussed using an L-curves analysis and we discuss the influence of the choice of the order of derivatives in the regularization terms for the description of the deep interior. We study the latitudinal resolution of the inversion of a-coefficients compared to that of the inversion of individual splittings built from these coefficients. Compared to the previous inversion of the first three months of LOWL data made by Tomczyk et al. (1995ApJ...448L..57T), our solution is extended up to the surface by adding high degree modes and constraining the rotation to fit the spectrographic observations (Snodgrass, 1984SPh....94...13S). In the radiative zone we obtain more rigid rotation and our solution is compatible with a rotation of the solar core of the order or smaller than the surface rotation at mid latitude. Title: Stokes Profile Asymmetries in Solar Active Regions Authors: Balasubramaniam, K. S.; Keil, S. L.; Tomczyk, S. Bibcode: 1997ApJ...482.1065B Altcode: Asymmetries in Stokes polarization spectral line profiles can be attributed to the existence of gradients in the velocity (and magnetic field) over the line-forming region. Models that solve the Stokes radiative transfer equations have incorporated both line-of-sight gradients and gradients perpendicular to the line of sight over the resolution element to produce the observed asymmetries. There have been only a few systematic studies of how these Stokes profile asymmetries vary across spatial structures and as a function of the amplitude of the velocity and magnetic fields, and very little statistical information is available. We present observational results from high spectral and spatial resolution Stokes V profile measurements made in an active region located near disk center and present correlations between the amplitude of the Stokes V asymmetry, the magnetic field strength, and line shifts and line asymmetries observed in the Stokes I profile. In regions where the field strength exceeds a few hundred gauss, we find a good correlation between the amplitude of the measured asymmetry in Stokes V and the observed shifts of the Stokes I profile. We also find a correlation between the asymmetry of the Stokes I profile and the amplitude of the Stokes V profile asymmetry. Title: Helioseismology by Genetic Forward Modeling Authors: Charbonneau, P.; Tomczyk, S. Bibcode: 1997ASPC..123...49C Altcode: 1997taca.conf...49C No abstract at ADS Title: Solar structure as revealed by 1 year LOWL data Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Schou, J.; Thompson, M. J.; Tomczyk, S. Bibcode: 1996BASI...24..147B Altcode: No abstract at ADS Title: Results from the LOWL instrument Authors: Schou, J.; Tomczyk, S.; Thompson, M. J. Bibcode: 1996BASI...24..375S Altcode: No abstract at ADS Title: Low-degree frequency splitting measurements and the rotation rate of the solar core Authors: Tomczyk, S.; Schou, J.; Thompson, M. J. Bibcode: 1996BASI...24..245T Altcode: No abstract at ADS Title: Measurement of the Rotation Rate in the Deep Solar Interior Authors: Tomczyk, S.; Schou, J.; Thompson, M. J. Bibcode: 1996AAS...188.6903T Altcode: 1996BAAS...28..935T We present a measurement of the rotation rate in the interior of the Sun based on two years of observations with the LOWL instrument. LOWL allows the observation of solar oscillations with degrees from 0 to 100, thus providing a homogeneous low- and intermediate-degree dataset. Significantly, it is able to make spatially resolved observations of low degree modes, thereby making it possible to separate the different modes within a given multiplet. This reduces the potential for systematic errors compared to observations using integrated sunlight. We have used observations of the frequency splittings of modes with degrees from 1 to 100 to infer the rotation rate in the solar interior with some radial resolution and without excessive errors. Over most of the interior we have also been able to estimate the latitudinal variation of the rotation rate. We confirm earlier findings that near the base of the convection zone the solar rotation profile undergoes a transition from surface-like differential rotation to a rotation rate that is independent of latitude. Additionally, we find that below the base of the convection zone our measurement is consistent with rigid body rotation at a rate somewhat lower than the surface equatorial rate. This measurement provides strong constraints on the theories of angular momentum transport in solar-type stars. Title: GONG Data: Implications for the Sun's Interior and Near Surface Magnetic Field Authors: Goode, P. R.; Dziembowski, W. A.; Rhodes, E. J., Jr.; Tomczyk, S.; Schou, J.; GONG Magnetic Effects Team Bibcode: 1996AAS...188.5307G Altcode: 1996BAAS...28..904G The solar oscillation spectrum and the fine structure in it from the first complete month of GONG data have been used to place a limit on the Sun's internal magnetic field. The limit is consistent with the magnetic pressure being no more than 1/1000 of the gas pressure between the Sun's deep interior and its surface. This conclusion is consistent with earlier results. The GONG data are from a time near magnetic activity minimum. The effect of the near surface magnetic field on the fine structure in the oscillation spectrum reflects a perturbation of quadrupole toroidal symmetry. This geometry also dominated at the last activity minimum. The meaning of this result is discussed. The near surface magnetic perturbation is not spherically symmetric. This corrupts the results of inversions designed to probe the Sun's deep interior. The solution to this problem is presented. Title: White Light Coronal Rotation Characteristics: 1984-1995 Authors: Hassler, D. M.; Tomczyk, S. Bibcode: 1996AAS...188.8006H Altcode: 1996BAAS...28..957H Time series of white light polarized brightness (pB) data from the HAO MkIII K-coronameter at Mauna Loa, Hawaii have been analyzed by direct Fourier analysis to study variations in the coronal rotation rate as a function of height, latitude, and time in the solar cycle. Short time series (ranging from 1-4 years) provide the ability to resolve or discriminate variations in the rotation rate at different times in the solar cycle while longer time series (i.e. 12 years) provide maximum signal-to-noise to study variations of rotation rate with height in the corona. Results suggest evidence of variations of the rotation rate with latitude and height, with more differential rotation and slightly faster mean rotation rates present at lower heights in the corona. Results also suggest variations of differential rotation and mean rotation rate with time in the solar cycle with slightly faster rotation rates during solar minimum. Title: The Solar Acoustic Spectrum and Eigenmode Parameters Authors: Hill, F.; Stark, P. B.; Stebbins, R. T.; Anderson, E. R.; Antia, H. M.; Brown, T. M.; Duvall, T. L., Jr.; Haber, D. A.; Harvey, J. W.; Hathaway, D. H.; Howe, R.; Hubbard, R. P.; Jones, H. P.; Kennedy, J. R.; Korzennik, S. G.; Kosovichev, A. G.; Leibacher, J. W.; Libbrecht, K. G.; Pintar, J. A.; Rhodes, E. J., Jr.; Schou, J.; Thompson, M. J.; Tomczyk, S.; Toner, C. G.; Toussaint, R.; Williams, W. E. Bibcode: 1996Sci...272.1292H Altcode: The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10-5. For a 3-year data set, the fractional error is expected to be 3 x 10-6. The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure. Title: The Sun's Hydrostatic Structure from LOWL Data Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Schou, J.; Thompson, M. J.; Tomczyk, S. Bibcode: 1996ApJ...460.1064B Altcode: Recent observations with the LOWL (Low-Degree [l] Oscillations Experiment) instrument have for the first time provided a uniform set of frequencies that allow detailed inversion for the structure of much of the Sun's deep interior. We present the results of inverting the LOWL data and compare them with the corresponding results obtained using inhomogeneous data sets from more than one instrument. Furthermore, improvements in the description of the required physics motivates the calculation of new solar models. Thus, we present results of inversions of the LOWL data against several reference models using up-to-date physics. In models including the gravitational settling of helium, the sound speed and density agree with the Sun to within substantially better than 1%. We test various modifications to the physics of the models in order to see if the remaining small (but significant) discrepancy between the Sun and the models can be removed. We find that none of the modifications tested can adequately account for the remaining discrepancy, though a small increase in helium diffusion in the core gives a modest improvement over the standard diffusion model. Finally, we find that the seismic data support theoretical calculations that indicate that settling of heavier elements has reduced the present surface value of Z by about 8% relative to its mean interior value. Title: Results From the LOWL Instrument Authors: Schou, J.; Tomczyk, S.; Thompson, M. J. Bibcode: 1995AAS...18710101S Altcode: 1995BAAS...27.1426S In this poster we will present various results from one year of observations with the LOWL instrument. The LOWL instrument is designed to observe oscillations with degrees l from 0 to about 100 providing a homogeneous dataset for inversions. Given the spatial resolution of the instrument it is possible to separate different azimuthal orders m even for the lowest degree modes, hopefully giving more accurate splittings than those determined using integrated sunlight for a similar time period. We will show the results of an inversion for the solar rotation rate between 0.1R_sun and 0.95R_sun. Given the long duration and the large number of terms used to describe the m-dependence of the mode frequencies we have been able to obtain very good resolution in both the radial direction and in latitude while keeping the statistical errors low, thereby obtaining more accurate results than previously possible. We will also present results of analyzing different parts of the time-series and compare the temporal variations in mode frequencies and splittings with variations in the solar activity. Title: Measurement of the Rotation Rate in the Deep Solar Interior Authors: Tomczyk, S.; Schou, J.; Thompson, M. J. Bibcode: 1995ApJ...448L..57T Altcode: We present a measurement of solar internal rotation based on observations obtained over 3 months in early 1994 with a new instrument called LOWL. This instrument allows for the simultaneous observation of low- and intermediate-degree solar oscillations with spatial resolution. We have measured the frequency splitting of 673 multiplets with degrees ranging from 1 to 80 and inverted these to derive an estimate of the solar internal rotation profile between 0.2 and 0.85 R⊙. The accuracy of this measurement ranges from ~1% in the outer regions to ~5% at 0.2 R⊙ and thus places better constraints than hitherto on the rotation in the deep solar interior. We confirm earlier findings that near the base of the convection zone the solar rotation profile undergoes a transition from surface-like differential rotation to a rotation rate that is independent of latitude. In addition, we find that from the base of the convection zone down to 0.2 R⊙ our measurement is consistent with rigid body rotation at a rate somewhat lower than the surface equatorial rate. The accuracy of our measurement in the deep solar interior provides a strong constraint to theories of solar and stellar angular momentum transport. Title: A Measurement of the Rotation Rate in the Deep Solar Interior Authors: Schou, J.; Tomczyk, S.; Thompson, M. J. Bibcode: 1995ESASP.376b.275S Altcode: 1995soho....2..275S; 1995help.confP.275S No abstract at ADS Title: Solar Structure Inversion with LOWL Data Authors: Basu, S.; Christensen-Dalsgaard, J.; Schou, J.; Thompson, M. J.; Tomczyk, S. Bibcode: 1995ESASP.376b..25B Altcode: 1995help.confP..25B; 1995soho....2...25B Presents inversion results for the radial hydrostatic structure of the Sun, using six months of oscillation data obtained with the LOWL instrument. Using modes with degrees from 0 to 90 and frequencies between 1.5 and 3.5 mHz, the authors have inferred the variation with depth of the sound speed, density ρ and u = p/ρ (p being pressure) from r = 0.05 Rsun to 0.85 Rsun. They find that in this region the sound speed in the Sun is within 0.15% of that of a model constructed using the MHD equation of state and OPAL opacities and incorporating helium diffusion. The density difference between Sun and model is less than 0.8%. Given the small error bars on the inversion results these small differences are significant, however. The solar sound speed appears to be higher than in the model for r < 0.2 Rsun . The authors speculate that this might indicate interesting physics in the inner core. Title: Constraining Solar Core Rotation with Genetic Forward Modelling Authors: Tomczyk, S.; Charbonneau, P.; Schou, J.; Thompson, M. J. Bibcode: 1995ESASP.376b.271T Altcode: 1995soho....2..271T; 1995help.confP.271T No abstract at ADS Title: An Instrument to Observe Low-Degree Solar Oscillations Authors: Tomczyk, S.; Streander, K.; Card, G.; Elmore, D.; Hull, H.; Cacciani, A. Bibcode: 1995SoPh..159....1T Altcode: We have constructed an instrument optimized to observe solar oscillations of low degree. The primary goal of this instrument, which we call LOWL, is to measure the frequency splitting of the low-degree modes in order to determine the rotation rate of the solar core. The LOWL is a Doppler imager based on a magneto-optical filter. It employs a two-beam technique to simultaneously observe solar images in opposite wings of the absorption line of potassium at 769.9 nm. This instrument is very stable against drifts in the wavelength zero-point, is insensitive to noise sources due to intensity fluctuations and image motion, and has a Doppler analyzer with no moving parts. The LOWL has been deployed at HAO's observing station on Mauna Loa, Hawaii and will operate for a period of at least two years. Title: Stokes Profile Asymmetries in Active Regions Authors: Balasubramaniam, K. S.; Keil, S. L.; Tomczyk, S.; Bernasconi, P. Bibcode: 1995SPD....26..205B Altcode: 1995BAAS...27..951B No abstract at ADS Title: Results from the LOWL Instrument Authors: Schou, J.; Tomczyk, S.; Thompson, M. J. Bibcode: 1995SPD....26..402S Altcode: 1995BAAS...27..954S No abstract at ADS Title: Spatially Resolved Observations of Low-Degree Solar Oscillations Authors: Tomczyk, S. Bibcode: 1995ASPC...76..444T Altcode: 1995gong.conf..444T No abstract at ADS Title: Preliminary Results from Observations with the LOWL Instrument Authors: Schou, J.; Tomczyk, S. Bibcode: 1995ASPC...76..448S Altcode: 1995gong.conf..448S No abstract at ADS Title: A Measurement of the Rotation Rate in the Deep Solar Interior Authors: Schou, J.; Tomczyk, S.; Thompson, M. J. Bibcode: 1994AAS...185.4401S Altcode: 1994BAAS...26Q1377S Measurements of the rotation rate in the deep solar interior using helioseismology have given inconsistent results, presumably due to problems with the algorithms used for the analysis of spatially unresolved observations of the oscillations. Here we present a measurement of the rotation rate in the interior of the Sun based on observations with a new instrument called LOWL. Unlike earlier instruments this instrument allows the observation of oscillations with degrees from 0 to ~ 80. In particular it is able to make spatially resolved observations of low degree modes, thereby making it possible to spatially separate the different modes within a given multiplet. This reduces the potential for systematic errors compared to observations using integrated sunlight. We have used observations of the frequency splittings of modes with degrees from 1 to 80 to infer the rotation rate in the solar interior down to ~ 0.2 R_⊙ with some radial resolution and without excessive errors. Over part of the range we have also been able to estimate the latitudinal variation of the rotation rate. This measurement provides strong constraints on the theories of solar and stellar angular momentum transport. Title: Simultaneous Filter and Spectrograph Observations of Active Regions with the Advanced Stokes Polarimeter Authors: Tomczyk, S.; Balasubramaniam, K. S.; Keil, Stephen L. Bibcode: 1994ASPC...68..262T Altcode: 1994sare.conf..262T No abstract at ADS Title: Requirements for the Observation of Low-Degree Solar Oscillations Authors: Veitzer, S. A.; Tomczyk, S.; Schou, J. Bibcode: 1993ASPC...42..465V Altcode: 1993gong.conf..465V No abstract at ADS Title: Early Results from HAO/NSO Advanced Stokes Polarimeter Authors: Lites, B. W.; Elmore, D. F.; Tomczyk, S.; Seagraves, P.; Skumanich, A.; Streander, K. V. Bibcode: 1993ASPC...46..173L Altcode: 1993mvfs.conf..173L; 1993IAUCo.141..173L No abstract at ADS Title: LOWL - an Instrument to Observe Low-Degree Solar Oscillations Authors: Tomczyk, S.; Cacciani, A.; Veitzer, S. A. Bibcode: 1993ASPC...42..469T Altcode: 1993gong.conf..469T No abstract at ADS Title: The Advanced Stokes Polarimeter - A new instrument for solar magnetic field research Authors: Elmore, D. F.; Lites, B. W.; Tomczyk, S.; Skumanich, A. P.; Dunn, R. B.; Schuenke, J. A.; Streander, K. V.; Leach, T. W.; Chambellan, C. W.; Hull, H. K. Bibcode: 1992SPIE.1746...22E Altcode: A new Stokes polarimeter for high spatial resolution quantitative measurement of magnetic fields at multiple heights in the solar atmosphere has been constructed by the National Center for Atmospheric Research and the National Solar Observatory. The instrument uses the Vacuum Tower Telescope at Sunspot, New Mexico, and its existing horizontal spectrograph, universal birefringment filter, and image motion stabilization system. The polarimeter uses a rotating retarder polarization modulator with polarization calibration optics. Multiple paired CCDs are used for detection followed by video processing to produce spatial maps of the full state of polarization in restricted regions of the solar spectrum. Two spectral regions encompassing lines sensitive to the Zeeman effect, which form in the photosphere and low chromosphere, are recorded simultaneously. Significant developments include: construction of the new telescope post focus optical arrangement, creation of a polarization model for the telescope, construction of high-speed, low-noise solid state cameras, and construction of computer hardware for receiving and processing high-rate 12-bit digital data. Title: The Advanced Stokes Polarimeter: A New Instrument for Solar Magnetic Field Research Authors: Tomczyk, S.; Elmore, D. F.; Lites, B. W.; Dunn, R. B.; Skumanich, A.; Schuenke, J. A.; Streander, K. V.; Leach, T. W.; Chambellan, C. W.; Lacey, L. B. Bibcode: 1992AAS...180.5108T Altcode: 1992BAAS...24..814T A new Stokes polarimeter for high spatial resolution quantitative measurement of magnetic fields at multiple heights in the solar atmosphere has been constructed by the National Center for Atmospheric Research and the National Solar Observatory. The instrument has become operational at the Vacuum Tower Telescope at Sunspot, New Mexico and uses its existing horizontal spectrograph, universal birefringent filter, and image motion stabilization system. To these optical systems we have added a rotating wave plate polarimeter and polarization calibration optics. Multiple CCDs are used for detection followed by video processing in order to produce polarization maps of solar regions from several spectrum lines simultaneously. Significant developments include: a) construction of the new VTT post focus optical arrangement, b) creation of a polarization model for the VTT, c) construction of high speed, low noise CCD cameras, and d) construction of computer hardware for receiving and processing high rate 12-bit digital data. Title: First Results from the Advanced Stokes Polarimeter Authors: Lites, B. W.; Dunn, R. B.; Elmore, D. F.; Tomczyk, S.; Skumanich, A.; Streander, K. V. Bibcode: 1992AAS...180.1201L Altcode: 1992BAAS...24..747L The Advanced Stokes Polarimeter (ASP) is a collaborative program between the High Altitude Observatory (HAO) and the National Solar Observatory (NSO) to investigate the physics of solar active regions though quantitative measurements of vector magnetic fields. First scientific results from the ASP were obtained during an observing run in March, 1992, when high resolution Stokes profile maps of active regions were obtained under good seeing conditions. The ASP measures simultaneously the full Stokes profiles in photospheric Fe I lines near 630 nm and in the temperature minimum/low chromospheric Mg I b-lines at 517 nm. We present scans of an isolated small sunspot near disk center, and we discuss the fine structure of the vector field within this sunspot and in the magnetic elements surrounding it. Observations of a complex active region near the east limb will also be presented. This active region produced a flare during the observational sequence. Title: Systematic errors in polarimeter calibration due to imperfect calibration optics. Authors: Tomczyk, S.; Stoltz, P.; Seagraves, P. Bibcode: 1991sopo.work..142T Altcode: The authors investigate systematic errors introduced in the calibration of a Stokes polarimeter when the calibration optics deviate from ideal. To accomplish this, they employ a linearized treatment of the Mueller calculus which allows for small and arbitrary imperfections in the Mueller matrices of the calibration optics, as well as a small amount of polarization in the calibration light source. The authors find that half of the response matrix elements contain systematic errors which can be related to imperfections in certain elements of the Mueller matrices of the calibration optics. Title: Preliminary results from the HAO/NSO Advanced Stokes Polarimeter prototype observing run. Authors: Lites, B. W.; Elmore, D.; Murphy, G.; Skumanich, A.; Tomczyk, S.; Dunn, R. B. Bibcode: 1991sopo.work....3L Altcode: A prototype version of the Advanced Stokes Polarimeter was operated at the Sunspot Vacuum Tower Telescope of the National Solar Observatory in May und June, 1990. Although the prototype instrument does not have the capability of the final instrument to be deployed in 1991, it nonetheless provided high spatial resolution Stokes profiles observations of a small symmetric sunspot. Analysis of these observations shows that the magnetic field at the outer edge of the penumbra of this sunspot is highly inclined with respect to the local normal (γ = 70 - 80°), in agreement with previous Stokes II measurements of larger sunspots. In addition, the axial field and flux distribution was found to be nearly identical to that of the previous Stokes II measurement. Title: Depth and Latitude Dependence of the Solar Internal Angular Velocity Authors: Rhodes, Edward J., Jr.; Cacciani, Alessandro; Korzennik, Sylvain; Tomczyk, Steven; Ulrich, Roger K.; Woodard, Martin F. Bibcode: 1990ApJ...351..687R Altcode: One of the design goals for the dedicated helioseismology observing state located at Mount Wilson Observatory was the measurement of the internal solar rotation using solar p-mode oscillations. In this paper, the first p-mode splittings obtained from Mount Wilson are reported and compared with those from several previously published studies. It is demonstrated that the present splittings agree quite well with composite frequency splittings obtained from the comparisons. The splittings suggest that the angular velocity in the solar equatorial plane is a function of depth below the photosphere. The latitudinal differential rotation pattern visible at the surface appears to persist at least throughout the solar convection zone. Title: Solar magnetic fields measurements with a magneto-optical filter. Authors: Cacciani, A.; Ricci, D.; Rosati, P.; Rhodes, E. J.; Smith, E.; Tomczyk, S.; Ulrich, R. K. Bibcode: 1990NCimC..13..125C Altcode: The presence of a magnetic field at different levels inside the Sun has crucial implications for helioseismology. The solar oscillation observing program carried out since 1983 at Mt. Wilson with Cacciani magneto-optical filter (MOF) has recently been modified to acquire full-disk magnetograms with 2 arcsec spatial resolution. The authors present a method for the correct determination of magnetic maps which are free of contamination by velocity signal. They show that no cross-talk exists between the Doppler and Zeeman shifts of the Na D lines, provided that instrumental polarization effects are taken into account. They also used the observed line-of sight photospheric field to map the vector field in the inner corona, above active regions, in the "current free" approximation. Title: An experiment to measure the solar ℓ = 1 rotational frequency splitting Authors: Cacciani, A.; Paverani, E.; Ricci, D.; Rosati, P.; Marquedant, R. M.; Smith, E. J.; Tomczyk, S. Bibcode: 1990LNP...367..197C Altcode: 1990psss.conf..197C To date, only integrated light experiments have attained the high signal-to-noise ratio and frequency resolution necessary to measure the rotational frequency splitting of low degree solar p-modes. These experiments, however, are limited by the finite mode linewidths coupled with the inability of non-imaging experiments to unambiguously separate prograde and retrograde modes. In particular, the separation of the prograde and retrograde mode frequencies of the very important = 1 spherical harmonic, dictates that the experiment have the capability to coarsely resolve the eastern from the western hemisphere of the solar disk. Initial attempts to attain the desired image resolution by masking the solar image at the focal plane of the telescope and chopping the two hemispheres on the detector have been unsuccessful due to the high velocity noise introduced by the solar rotation through image motions and guiding instabilities. In this paper we present the concept of what we call spectroscopic masking, which provides the ability to filter oscillation modes spectroscopically, and without the need to image the Sun. This results in an optical configuration which is insensitive to image motions and guiding errors while still providing adequate spatial resolution to separate prograde and retrograde = 1 modes. A conceptual study will be presented along with a test observing run showing the quality of the achievable data. Title: Measurement of the rotational frequency splitting of the solar five-minute oscillations from magneto-optical filter observations. Authors: Tomczyk, Steven; Cacciani, Alessandro; Korzennik, Sylvain G.; Rhodes, Edward J., Jr.; Ulrich, Roger K. Bibcode: 1988ESASP.286..141T Altcode: 1988ssls.rept..141T Observations of the solar five-minute oscillations in the photospheric velocity field were obtained during the summer of 1984 at the 60-foot solar tower of the Mt. Wilson Observatory with a magneto-optical filter. The magneto-optical filter employs magneto-optical effects in an atomic vapor to isolate narrow bandpasses in alternate wings of a spectral line. Time series of full disk velocity images having a resolution of about 10 arcseconds and a noise level of 15 m/s/pixel were obtained on 92 days between the months of May and September of 1984. A subset of two time series from this data of 16 and 19 days duration having a total of 25744 doppler images were analyzed to provide estimates of the rotational frequency splitting for spherical harmonic degrees between 5 and 120. The results of this analysis indicate a decrease in the rate of solar rotation with increasing depth inside the sun. Also, a decrease in the rate of differential rotation with increasing depth is observed. Title: Inversion of the solar rotation rate versus depth and latitude. Authors: Korzennik, Sylvain G.; Cacciani, Alessandro; Rhodes, Edward J., Jr.; Tomczyk, Steven; Ulrich, Roger K. Bibcode: 1988ESASP.286..117K Altcode: 1988ssls.rept..117K The authors have used three different inversion techniques to compute the internal solar rotation rate from several sets of n-averaged frequency splittings. They have used an iterative variation of the spectral expansion method, the optimal averaging kernel method and a piecewise constant constrained least square method to invert the data. Each computation was carried out independently. While they present similar trends, each of the solutions differs in detail. A consistent feature in all the inversions is the disappearance of differential rotation below the base of the convection zone. Also, a strong differential signature in the deeper part of the convection zone is present in most of the solutions. A slow decrease of the rotation rate with depth for the equatorial and mid-latitude curves is significant in the spectral expansion and the least square results but only marginally apparent in the averaging kernel results. Title: Acquisition and reduction procedures for MOF Doppler-magnetograms. Authors: Cacciani, Alessandro; Ricci, D.; Rosati, P.; Rhodes, Edward J., Jr.; Smith, E.; Tomczyk, Steven; Ulrich, Roger K. Bibcode: 1988ESASP.286..185C Altcode: 1988ssls.rept..185C The authors analyse defects occurred on the MOF first magnetograms, particularly they discuss the problem of the apparent contamination between velocity and magnetic fields. They find that a correct acquisition and reduction procedure gives cleaner results. The authors also suggest a new vector magnetograph and compute the vector field at coronal levels using one MOF longitudinal magnetogram. Title: Radial and latitudinal gradients in the solar internal angular velocity. Authors: Rhodes, Edward J., Jr.; Cacciani, Alessandro; Korzennik, Sylvain G.; Tomczyk, Steven; Ulrich, Roger K.; Woodard, Martin F. Bibcode: 1988ESASP.286...73R Altcode: 1988ssls.rept...73R The authors recently presented the results of an analysis of the frequency splittings of intermediate-degree (3 < degree ≤ 170) p-mode oscillations which were obtained from a 16-day subset of our 1984 Mt. Wilson 60-foot tower observations. These results showed evidence for both radial and latitudinal gradients in the solar internal angular velocity. In particular, the results indicated that, from 0.6 Rsun to 0.95 Rsun, the solar internal angular velocity increases systematically from 440 to 463 nHz, corresponding to a positive radial gradient of ≍66 nHz/Rsun for that portion of the solar interior. A previous analysis indicated that the latitudinal differential rotation gradient which is seen at the solar surface persists throughout the convection zone, although there was some indication that the differential rotation might disappear entirely below the base of the convection zone. Here the authors extend their previous analysis to include comparisons with additional observational studies and they also present comparisons between our earlier results and the results of additional inversions of several of the observational datasets. All of these comparisons reinforce the previous conclusions regarding the existence of radial and latitudinal gradients in the internal angular velocity. Title: Full-Disk Magnetograms Obtained with a Na Magneto-Optical Filter at the Mount Wilson Observatory Authors: Rhodes, E. J.; Cacciani, A.; Garneau, G.; Misch, T.; Progovac, D.; Shieber, T.; Tomczyk, S.; Ulrich, R. K. Bibcode: 1988BAAS...20..744R Altcode: No abstract at ADS Title: On the Constancy of Intermediate-Degree p-Mode Frequencies during the Declining Phase of Solar Cycle 21 Authors: Rhodes, Edward J., Jr.; Woodard, Martin F.; Cacciani, Alessandro; Tomczyk, Steven; Korzennik, Sylvain G.; Ulrich, Roger K. Bibcode: 1988ApJ...326..479R Altcode: A comparison of two sets of frequencies of intermediate-degree (6 ≤ l ≤ 89) solar p-mode oscillations obtained in late 1981 and in mid-1984 shows agreement at the level of 0.02 μHz, or better than one part in 105. In particular, the frequencies of 573 modes obtained at the South Pole during 1981 December 24 - 25, (reported by Duvall, Harvey, and Pomerantz in 1987) were compared with the frequencies of the same modes as observed at the Mount Wilson Observatory 60 foot Solar Tower from 1984 July 29 through August 13. It is concluded that the data are consistent with no change in intermediate-degree p-mode frequencies between late 1981 and mid-1985. Title: Full-Disk Solar Dopplergrams Observed with a 1024X1024 Pixel CCD Camera Authors: Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S. Bibcode: 1988IAUS..123..471R Altcode: The authors present here the first full-disk solar Dopplergram obtained with the new 1024×1024-pixel CCD camera which has recently been installed at the 60 foot Tower Telescope of the Mt. Wilson Observatory. Title: Measurements of Solar Internal Rotation Obtained with the Mt-Wilson 60-FOOT Solar Tower Authors: Rhodes, E. J., Jr.; Cacciani, A.; Woodard, M.; Tomczyk, S.; Korzennik, S.; Ulrich, R. K. Bibcode: 1988IAUS..123...41R Altcode: The authors have obtained estimates of the solar internal rotational velocity from measurements of the frequency splittings of p-mode oscillations. Specifically, they have analyzed a 10-day time series of full-disk Dopplergrams obtained during July and August 1984 at the 60-Foot Tower Telescope of the Mt. Wilson Observatory. Title: A Measurement of the Rotational Frequency Splitting of the Solar Five-Minute Oscillations. Authors: Tomczyk, Steven Bibcode: 1988PhDT.........1T Altcode: Observations of the solar five-minute acoustic oscillations were employed to probe the sub-surface rotation rate of the sun. The oscillations were observed in the solar photospheric velocity field. Full disk velocity images were obtained with a magneto-optical filter which employs magneto-optical effects in an atomic vapor of sodium to isolate alternate wings of a spectral line. The observations were obtained at the 60-foot Solar Tower of the Mt. Wilson Observatory during the summer of 1984. The time series of velocity images were analyzed to yield the rotational frequency splitting of oscillation modes with spherical harmonic degrees ranging from 5 to 120. These results show the solar rotation rate to decrease with depth inside the sun over the depth range studied. Also, the rate of differential rotation is observed to decrease with depth inside the sun. Title: Constancy of Intermediate-degree p-Mode Frequencies During the Declining Phase of Solar Cycle 21 Authors: Rhodes, E. J., Jr.; Woodard, M. F.; Cacciani, A.; Tomczyk, S.; Korzennik, S.; Ulrich, R. K. Bibcode: 1987BAAS...19Q.933R Altcode: No abstract at ADS Title: Angular Velocity of the Solar Interior Obtained by an Asymptotic Inversion of P-Mode Frequency Shifts Authors: Woodard, M. F.; Rhodes, E. J., Jr.; Tomczyk, S.; Korzennik, S.; Cacciani, A.; Ulrich, R. K. Bibcode: 1987BAAS...19..934W Altcode: No abstract at ADS Title: A Magneto-Optical Filter for Solar Oscillation Measurements Authors: Tomczyk, S.; Cacciani, A.; Rhodes, E. J., Jr. Bibcode: 1987BAAS...19..701T Altcode: No abstract at ADS Title: Estimates of the solar internal angular velocity obtained with the Mt. Wilson 60-foot solar tower Authors: Rhodes, Edward J., Jr.; Cacciani, Alessandro; Woodard, Martin; Tomczyk, Steven; Korzennik, Sylvain; Ulrich, R. K. Bibcode: 1987ASSL..137...75R Altcode: 1987isav.symp...75R Estimates are obtained of the solar internal angular velocity from measurements of the frequency splittings of p-mode oscillations. A 16-day time series of full-disk Dopplergrams obtained during July and August 1984 at the 60-foot tower telescope of the Mt. Wilson Observatory is analyzed. Power spectra were computed for all of the zonal, tesseral, and sectoral p-modes from l = 0 to 89 and for all of the sectoral p-modes from l = 90 to 200. A mean power spectrum was calculated for each degree up to 89. The frequency differences of all of the different nonzonal modes were calculated for these mean power spectra. Title: Full-disk solar dopplergrams observed with a one megapixel CCD camera and sodium magnetooptical filter Authors: Rhodes, Edward J., Jr.; Cacciani, Alessandro; Tomczyk, Steven Bibcode: 1987ASSL..137...69R Altcode: 1987isav.symp...69R The paper presents here the first two full-disk solar Dopplergrams obtained with the new 1024 x 1024-pixel CCD camera which has recently been installed at the 60-Foot Tower Telescope of the Mt. Wilson Observatory. These Dopplergrams have a spatial resolution of 2.2 arcseconds and were obtained in a total of one minute of time. The Dopplergrams were obtained with a magnetooptical filter which was designed to obtain images in the two Na D lines. The filter and the camera were operated together as part of the development of a solar oscillations imager experiment which is currently being designed at JPL for the Joint NASA/ESA Solar and Heliospheric Observatory mission. Two different images obtained by subtracting two pairs of the Dopplergrams from the initial time series are also included. Title: Evidence for Radial Gradients in the Solar Internal Rotational Velocity Authors: Rhodes, E. J., Jr.; Tomczyk, S.; Woodard, M. F.; Cacciani, A.; Korzennik, S.; Ulrich, R. K. Bibcode: 1986BAAS...18Q1010R Altcode: No abstract at ADS Title: Applications of the magneto-optical filter to stellar pulsation measurements Authors: Rhodes, Edward J., Jr.; Cacciani, Alessandro; Tomczyk, Steven Bibcode: 1986ASIC..169..359R Altcode: 1986ssds.proc..359R A proposed method of employing the Cacciani magneto-optical filter (MOF) for stellar seismology studies is described. The method relies on the fact that the separation of the filter bandpasses in the MOF can be changed by varying the level of input power to the filter cells. With the use of a simple servosystem the bandpass of a MOF can be tuned to compensate for the changes in the radial velocity of a star introduced by the orbital motion of the earth. Such a tuned filter can then be used to record intensity fluctuations through the MOF bandpass over an extended period of time for each given star. Also, the use of a two cell version of the MOF makes it possible to alternately chop between the bandpass located in the stellar line wing and a second bandpass located in the stellar continuum. Rapid interchange between the two channels makes it possible for atmospheric-introduced noise to be removed from the time series. Title: A one-megapixel image acquisition and processing system for solar oscillation studies. Authors: Rhodes, Edward J., Jr.; Bursch, Thomas K.; Ulrich, Roger K.; Tomczyk, Steven Bibcode: 1986SPIE..627..256R Altcode: The 1-Mpixel image acquisition and processing system that has been installed at the Mt. Wilson observatory as part of the development effort for the NASA/ESA Solar Oscillations Imager Experiment of the projected Heliospheric Observatory mission is discussed. The system encompasses a high speed CCD camera with a 1024 x 1024-pixel virtual phase chip array, yielding a readout rate of about 800,000 pixels/sec; this allows the entire Mpixel array to be read out in just over 1 sec. The camera is interfaced with a floating point array processor that integrates several successive exposures from the CCD camera and differences selected pairs of integrated images. The system is currently being used to record and difference narrowband images of the sun. Title: The 1984 solar oscillation program of the Mt. Wilson 60-foot tower. Authors: Rhodes, Edward J., Jr.; Cacciani, Alessandro; Tomczyk, Steven; Ulrich, Roger K. Bibcode: 1986ASIC..169..309R Altcode: 1986ssds.proc..309R The authors describe the instrumentation, data, and preliminary results from the summer, 1984, solar oscillation observing program which was carried out using the 60-foot tower telescope of the Mt. Wilson Observatory. Title: The effects of seeing on noise Authors: Ulrich, R. K.; Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S. Bibcode: 1985sses.nasa..263U Altcode: The effect of the supergranulation velocity field combined with seeing smearing of the solar image on the measurement of solar oscillations is discussed. Depending on the nature of the observational velocity determination scheme, the image motions can shift the background velocity pattern and produce a source of noise that reduces the quality of the observations. The magnitude of this effect is estimated and observational results which are consistent with this estimate are presented. Title: The 1984 solar oscillation program of the Mount Wilson 60-foot tower Authors: Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S.; Ulrich, R. K. Bibcode: 1985STIN...8612195R Altcode: The instrumentation, data, and preliminary results from the summer, 1984, solar oscillation observing program which was carried out using the 60-foot tower telescope of the Mt. Wilson Observatory are described. This program was carried out with a dedicated solar oscillation observing system and obtained full-disk Dopplergrams every 40 seconds for up to 11 hours per day. Between June and September, 1984, observations were obtained with a Na magneto-optical filter on 90 different days. The data analysis has progressed to the point that spherical harmonic filter functions were employed to generate a few one-dimensional power spectra from a single day's observations. Title: Evaluation of a magneto-optical filter and a Fabry-Perot interferometer for the measurement of solar velocity fields from space. Authors: Rhodes, E. J., Jr.; Cacciani, A.; Blamont, J.; Tomczyk, S.; Ulrich, R. K.; Howard, R. F. Bibcode: 1984sses.nasa..125R Altcode: 1984sss..conf..125R A program was developed to evaluate the performance of three different devices as possible space-borne solar velocity field imagers. Two of these three devices, a magneto-optical filter and a molecular adherence Fabry-Perot interferometer were installed in a newly-constructed observing system located at the 60-foot tower telescope at the Mt. Wilson Observatory. Time series of solar filtergrams and Dopplergrams lasting up to 10 hours per day were obtained with the filter while shorter runs were obtained with the Fabry-Perot. Two-dimensional k h-omega power spectra which show clearly the well-known p-mode ridges were computed from the time series obtained with the magneto-optical filter. These power spectra were compared with similar power spectra obtained recently with the 13.7-m McMath spectrograph at Kitt Peak. Title: Applications of the magneto-optical filter to stellar pulsation measurements Authors: Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S. Bibcode: 1984STIN...8612187R Altcode: A proposed method of employing the Cacciani magneto-optical filter (MOF) for stellar seismology studies is described. The method relies on the fact that the separation of the filter bandpasses in the MOF can be changed by varying the level of input power to the filter cells. With the use of a simple servosystem the bandpass of a MOF can be tuned to compensate for the changes in the radial velocity of a star introduced by the orbital motion of the Earth. Such a tuned filter can then be used to record intensity fluctuations through the MOF bandpass over an extended period of time for each given star. Also, the use of a two cell version of the MOF makes it possible to alternately chop between the bandpass located in the stellar line wing and a second bandpass located in the stellar continuum. Rapid interchange between the two channels makes it possible for atmospheric-introduced noise to be removed from the time series. Title: The effects of seeing on noise. Authors: Ulrich, R. K.; Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S. Bibcode: 1984sses.nasa..263U Altcode: 1984sss..conf..263U The authors discuss the effect of the supergranulation velocity field combined with seeing smearing of the solar image on the measurement of solar oscillations. Depending on the nature of the observational velocity determination scheme, the image motions can shift the background velocity pattern and produce a source of noise that reduces the quality of the observations. The authors give a rough estimate for the magnitude of this effect and present observational results which are consistent with this estimate. Title: Observations of Solar Velocity Fields With Large-Format CCD Cameras at the Mount Wilson Observatory Authors: Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S.; Ulrich, R. K.; Dumont, P.; Howard, R. F. Bibcode: 1984BAAS...16..979R Altcode: No abstract at ADS Title: The Summer 1984 Solar Oscillation Program of the Mount Wilson 60-foot Solar Telescope Authors: Tomczyk, S.; Rhodes, E. J., Jr.; Cacciani, A.; Ulrich, R. K.; Howard, R. F. Bibcode: 1984BAAS...16..978T Altcode: No abstract at ADS Title: Magneto-Optical Filter Observations of Solar Oscillations at the Mt. Wilson Observatory Authors: Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S.; Ulrich, R. K.; Dumont, P.; Howard, R. F. Bibcode: 1984BAAS...16..451R Altcode: No abstract at ADS Title: A compact dopplergraph/magnetograph suitable for space-based measurements of solar oscillations and magnetic fields Authors: Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S.; Ulrich, R. K.; Blamont, J.; Howard, R. F.; Dumont, P.; Smith, E. J. Bibcode: 1984AdSpR...4h.103R Altcode: 1984AdSpR...4..103R A compact Dopplergraph/magnetograph placed in a continuous solar-viewing orbit will allow us to make major advancements in our understanding of solar internal structure and dynamics. An international program is currently being conducted at JPL and Mt. Wilson to develop such an instrument. By combining a unique magneto-optical resonance filter with CID and CCD cameras we have been able to obtain full- and partial-disk Dopplergrams and magnetograms. Time series of the velocity images are converted into k-ω power spectra which show clear- the solar nonradial p-mode oscillations. Magnetograms suitable for studying the long-term evolution of solar active regions have also been obtained with this instrument. A flight instrument based on this concept is being studied for possible inclusion in the SOHO mission. Title: The analysis of solar models: Neutrinos and oscillations Authors: Ulrich, R. K.; Rhodes, E. J., Jr.; Tomczyk, S.; Dumont, P. J.; Brunish, W. M. Bibcode: 1983STIN...8427652U Altcode: Tests of solar neutrino flux and solar oscillation frequencies were used to assess standard stellar structure theory. Standard and non-standard solar models are enumerated and discussed. The field of solar seismology, wherein the solar interior is studied from the measurement of solar oscillations, is introduced. Title: Narrow- and intermediate-band Hα and O I λ7774 photometry andreticon spectroscopy of SX Cassiopeiae. Authors: Guinan, E. F.; Tomczyk, S.; Turnshek, D. J. Bibcode: 1983PASP...95..364G Altcode: Observations of the 36.57-day eclipsing binary SX Cas made on eight nights during February and March 1979 with pairs of intermediate- and narrow-band filters centered on the wavelengths of the Balmer H-alpha line and the O I 7774 A triplet are discussed. In addition, a reticon spectrum covering a wavelength range of 4750 A to 7700 A was obtained in September 1979, showing strong H-beta and H-alpha emission lines as well as absorption features of the K-giant component of the system. From the photometry, strong H-alpha emission is found at all the orbital phases sampled. However, no appreciable O I 7774 A line emission is detected. It is noted that the strong H-alpha emission is consistent with the presence of significant amounts of circumstellar and circumbinary gas. From the observations, it appears that the H-alpha emitting region is centered chiefly on the primary component, but the gas is partially eclipsed by the larger cool giant during primary eclipse. The H-alpha-emitting region therefore appears larger than the dimensions of the stellar components. In addition, the apparent nonrepeatability of the H-alpha emission strength from one orbital cycle to the next implies that relatively rapid changes in the extent or quantity of gas occur in the system. Title: Evidence for starspots on the DK Draconis (HR 4665). Authors: Guinan, E. F.; McCook, G. P.; Fragola, J. L.; Odonnell, W. C.; Tomczyk, S.; Weisenberger, A. G. Bibcode: 1982AJ.....87..893G Altcode: Observations of the long-period RS CVn-type binary DK Dra from February through September 1978 are presented. Light variations appear to be quasisinusoidal with a period of 64.6 + or - 0.4 d, and cycle-to-cycle changes in the character of the light curve have most likely occurred. No evidence of H-alpha or O I emission is found. A starspot model is used to generate theoretical light curves which fit those observed. Results indicate that the minimum spotted area is about 8% of the stellar surface area, which suggests that the fractional spotted area is at least 40-80 times greater for DK Dra than the total fractional area on the sun at sunspot maximum. An analysis of multibandpass data shows that the temperature difference between the photosphere and spot is about 1100 K. Title: The Sensitivity of Eigenfrequencies of Intermediate L Solar Oscillations to Solar Structure Authors: Ulrich, R. K.; Tomczyk, S.; Rhodes, E. J., Jr. Bibcode: 1982pccv.conf..138U Altcode: No abstract at ADS Title: The analysis of solar models - neutrinos and oscillations. Authors: Ulrich, R. K.; Rhodes, E. J., Jr.; Tomczyk, S.; Dumont, P. J.; Brunish, W. M. Bibcode: 1982AIPC...96...66U Altcode: No abstract at ADS Title: The Period Variability of SX Cassiopeiae Authors: Guinan, E. F.; Tomczyk, S. Bibcode: 1979IBVS.1623....1G Altcode: No abstract at ADS Title: Hydrogen shell flashes in massive accreting white dwarfs. Authors: Sion, E. M.; Acierno, M. J.; Tomczyk, S. Bibcode: 1979ApJ...230..832S Altcode: In the present paper, the long-term evolution of massive accreting white dwarfs in close binary systems is discussed in context of several astrophysical problems. It is shown that high surface luminosity models with spherically symmetric accretion (rather than disk accretion) yield very short interflash periods for massive white dwarfs accreting at high rates. The shell flashes exhibited by the models are not strong enough to eject mass, as in classical novae. However, the repetitive hydrogen shell flashes with an interflash period of 17 years may be relevant to understanding the underlying variability of the blue component of symbiotic variables if the blue component is a white dwarf. Title: Nova Cygni 1978 Authors: Guinan, E. F.; McCook, G. P.; Tomczyk, S.; de Young, J.; Morgan, J.; Mattei, M.; Wallentinsen, D.; Hawley, W.; Collins, P. L.; Peltier, L. C.; Hurless, C. Bibcode: 1978IAUC.3274....1G Altcode: E. F. Guinan, G. P. McCook and S. Tomczyk, Department of Astronomy, Villanova University, write: "Photoelectric wide- and narrow-band 6565 and 7774 A observations of Nova Cyg 1978 were made at Villanova University Observatory on Sept. 15.04-15.12 and 16.03-16.16 UT. Observations indicate variations in the wide-bandpasses of ~ 0.08 magnitude over the first night and of less than ~ 0.03 magnitude on the second night. The apparent brightnesses were about the same on both nights. An increase in net emission at H-alpha and at O I (7774 A) was also observed between the two nights." Corrigendum. On IAUC 3270, line 19, for strong structure at 3920 A read strong structure at 3820 A. Visual magnitude estimates: Sept. 19.03 UT, 7.6 (J. De Young, Huntington, WV); 19.16, 7.7 (J. Morgan, Prescott, AZ); 20.16, 7.7 (M. Mattei, Littleton, MA); 20.39, 7.6 (D. Wallentinsen, Albuquerque, NM); 21.11, 8.2 (W. Hawley, Concord, NH); 22.35, 8.0 (P. L. Collins, Mount Hopkins Observatory); 23.03, 8.2 (L. C. Peltier, Delphos, OH); 24.02, 8.3 (C. Hurless, Lima, OH). Title: Hα Photometry of X Persei Authors: Guinan, E. F.; McCook, G. P.; Acierno, M.; del Conte, R.; Lupie, O.; Tomczyk, S.; Young, K.; Dorren, J. D.; Siah, M. J. Bibcode: 1978BAAS...10..632G Altcode: No abstract at ADS Title: Evolutionary Models of Accreting Massive White Dwarfs. Authors: Sion, E. M.; Acierno, M.; Tomczyk, S. Bibcode: 1977BAAS....9R.634S Altcode: No abstract at ADS