Author name code: madsen ADS astronomy entries on 2022-09-14 author:"Madsen, Chad Allen" ------------------------------------------------------------------------ Title: The Airborne Infrared Spectrometer: Development, Characterization, and the 2017 August 21 Eclipse Observation Authors: Samra, Jenna E.; Marquez, Vanessa; Cheimets, Peter; DeLuca, Edward E.; Golub, Leon; Hannigan, James W.; Madsen, Chad A.; Vira, Alisha; Adams, Arn Bibcode: 2022AJ....164...39S Altcode: 2021arXiv210509419S On 2017 August 21, the Airborne Infrared Spectrometer (AIR-Spec) observed the total solar eclipse at an altitude of 14 km from aboard the NSF/NCAR Gulfstream V research aircraft. The instrument successfully observed the five coronal emission lines that it was designed to measure: Si X 1.431 μm, S XI 1.921 μm, Fe IX 2.853 μm, Mg VIII 3.028 μm, and Si IX 3.935 μm. Characterizing these magnetically sensitive emission lines is an important first step in designing future instruments to monitor the coronal magnetic field, which drives space weather events, as well as coronal heating, structure, and dynamics. The AIR-Spec instrument includes an image stabilization system, feed telescope, grating spectrometer, and slit-jaw imager. This paper details the instrument design, optical alignment method, image processing, and data calibration approach. The eclipse observations are described and the available data are summarized. Title: New Observations of the IR Emission Corona from the 2019 July 2 Eclipse Flight of the Airborne Infrared Spectrometer Authors: Samra, Jenna E.; Madsen, Chad A.; Cheimets, Peter; DeLuca, Edward E.; Golub, Leon; Marquez, Vanessa; Reyes, Naylynn Tañón Bibcode: 2022ApJ...933...82S Altcode: 2021arXiv210608760S The Airborne Infrared Spectrometer (AIR-Spec) was commissioned during the 2017 total solar eclipse, when it observed five infrared coronal emission lines from a Gulfstream V research jet owned by the National Science Foundation and operated by the National Center for Atmospheric Research. The second AIR-Spec research flight took place during the 2019 July 2 total solar eclipse across the south Pacific. The 2019 eclipse flight resulted in seven minutes of observations, during which the instrument measured all four of its target emission lines: S XI 1.393 μm, Si X 1.431 μm, S XI 1.921 μm, and Fe IX 2.853 μm. The 1.393 μm S XI line was detected for the first time, and probable first detections were made of Si XI 1.934 μm and Fe X 1.947 μm. The 2017 AIR-Spec detection of Fe IX was confirmed and the first observations were made of the Fe IX line intensity as a function of solar radius. Telluric absorption features were used to calibrate the wavelength mapping, instrumental broadening, and throughput of the instrument. AIR-Spec underwent significant upgrades in preparation for the 2019 eclipse observation. The thermal background was reduced by a factor of 30, providing a 5.5× improvement in signal-to-noise ratio, and the postprocessed pointing stability was improved by a factor of 5 to <10″ rms. In addition, two imaging artifacts were identified and resolved, improving the spectral resolution and making the 2019 data easier to interpret. Title: Exploring the middle corona: new instrumentation to address science questions critical to understanding the thermal structure and dynamic evolution of the middle corona Authors: DeLuca, Edward; Winebarger, Amy; Reeves, Katharine; Golub, Leon; Samra, Jenna; Madsen, Chad; Rivera, Yeimy; Karna, Nishu; Savage, Sabrina; Seaton, Daniel; West, Matthew; Downs, Cooper; Del Zanna, Giulio Bibcode: 2021AGUFMSH25F2150D Altcode: The global structure of the largely unexplored middle corona determines the physical properties of the inner heliosphere, affects the formation and acceleration of the solar wind, and controls the dynamics of eruptive events. Tracing the short and long term global evolution of the extended corona, identifying changes in corona/heliosphere connectivity and following the dynamic evolution of eruptive events in this unexplored region will provide observational data that will clarify how the corona transitions from closed to open, illuminate the genesis of coronal mass ejections, and provide input for the design of the next generation of physics based space weather forecasts. This poster outlines several critical science questions and identifies the measurements that are required to make substantial progress towards addressing the questions. We review and discuss the instrumentation necessary to capture the observations needed for meaningful progress in this area as well as the role of simulations in the interpretation of the observations. Title: Probing the Lower Solar Chromosphere Via Dynamical Signatures of UV Bursts in Cold Lines Authors: Chaparro, Victoria; Madsen, Chad; DeLuca, Edward Bibcode: 2021AGUFMSH45B2368C Altcode: UV Bursts are small scale brightenings identified by dramatic intensification and broadening of emission lines often accompanied by absorption features from cold metallic ions. They can be used as probes of plasma conditions in the lower solar atmosphere since their spectral features suggest they are magnetic reconnection events in the cool lower chromosphere. We present a spatial and temporal analysis of the intensification and broadening of the Si IV 1393.78 Å and Cl I 1351.66 Å lines observed by the Interface Region Imaging Spectrograph (IRIS) to trace magnetic reconnection outflows through the lower chromosphere. We employ a semi-automated UV burst detection algorithm by applying single-Gaussian fits (SGF) to the Si IV 1394 Å line in IRIS sit-and-stare data. We first isolate the likely candidate population in the SGF parameter space, reducing the candidate field from hundreds of thousands to only a few thousand spectra. We then manually search these candidate spectra for Ni II 1393.33 Å absorption. Following detection, we focus on the Cl I 1391.66 Å line to observe the influence of UV bursts over lower chromospheric dynamics. This is done by constructing a series of space-time plots of the peak intensity, Doppler velocity, and line width SGF parameters of Cl I 1391.66 Å to measure time lags between its intensification and broadening, allowing us to estimate downflow velocities in the lower chromosphere under UV burst conditions. This is possible because the peak intensity of Cl I 1391.66 Å is dependent on fluorescence from C II 1335.71 Å, a line strongly emitted by the UV burst source, while its width only broadens when the emitting material is impacted by a material flow. This study establishes the power of UV bursts as probes of dynamical phenomena in the lower chromosphere, a region that is notoriously difficult to observe directly. Furthermore, it lays the groundwork for future exploration of the often overlooked cool emission lines in the IRIS spectral passbands and their potential as physical diagnostics. This work is part of the NSF-REU Solar Physics program at SAO, grant number AGS-1850750. Keywords: Solar Magnetic Reconnection, Active Solar Chromosphere, Solar Ultraviolet Emission. Title: An Airborne Coronal Emission Surveyor (ACES) for Total Solar Eclipse Observations Authors: Samra, Jenna; Cheimets, Peter; DeLuca, Edward; Madsen, Chad; Marquez, Vanessa Bibcode: 2021AGUFMED13B..01S Altcode: The Airborne Coronal Emission Surveyor (ACES) is a new imaging Fourier transform spectrometer (FTS) that will explore the large-scale coronal infrared (IR) emission spectrum during the April 8, 2024 total solar eclipse. ACES will fly along the path of totality on the NSF/NCAR Gulfstream V High-performance Instrumented Airborne Platform for Environmental Research (GV HIAPER), with a stabilized solar feed provided by the Airborne Stabilized Platform for InfraRed Experiments (ASPIRE). During the 6-minute total eclipse, ACES will map emission line intensity in the 14 micron wavelength region at over a 0.73 0.5 field of view (FOV). A GV altitude of at least 13 km will enable it to survey the near and mid-IR with minimal atmospheric interference. ACES is the latest in a line of NSF-funded airborne instruments developed by Smithsonian Astrophysical Observatory to explore the IR emission corona from GV HIAPER. Previous instruments include the Airborne InfraRed Spectrometer (AIR-Spec), a cryogenic grating spectrometer that observed the 2017 and 2019 eclipses, and ASPIRE, which improves on the AIR-Spec image stabilization system to provide a 20 cm solar feed stabilized to 5 arcsec RMS over 1 second. Unlike AIR-Spec, which observed a narrow range of wavelengths and imaged along only one dimension, ACES will survey the entire 14 micron (2,50010,000 cm-1) spectral range at high (0.2 cm-1) spectral resolution and in two spatial dimensions. ACES is expected to observe neutral helium as well as 18 forbidden lines of ionized magnesium, silicon, sulfur, argon, calcium, and iron, and it may measure weaker lines of those and other ions. The mission addresses science questions related to the strength of different emission lines in different regions of the corona, the relative radiative to collisional excitation in each line, the best temperature and density diagnostics in the passband, and the variation of elemental abundances across the corona. The instrument consists of a condenser telescope, cryogenic Michaelson interferometer, achromatic lens, and IR camera. The 2024 eclipse flight will serve as the ACES commissioning flight. Title: Calibration of the Marshall Grazing Incidence X-Ray Spectrometer Experiment. II. Flight Instrument Calibration Authors: Athiray, P. S.; Winebarger, Amy R.; Champey, Patrick; Kobayashi, Ken; Savage, Sabrina; Beabout, Brent; Beabout, Dyana; Broadway, David; Bruccoleri, Alexander R.; Cheimets, Peter; Golub, Leon; Gullikson, Eric; Haight, Harlan; Heilmann, Ralf K.; Hertz, Edward; Hogue, William; Johnson, Steven; Kegley, Jeffrey; Kolodziejczak, Jeffery; Madsen, Chad; Schattenburg, Mark L.; Siler, Richard; Vigil, Genevieve D.; Wright, Ernest Bibcode: 2021ApJ...922...65A Altcode: The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a sounding rocket experiment that observes the soft X-ray spectrum of the Sun from 6.0-24 Å (0.5-2.0 keV), successfully launched on 2021 July 30. End-to-end alignment of the flight instrument and calibration experiments are carried out using the X-ray and Cryogenic Facility at NASA Marshall Space Flight Center. In this paper, we present the calibration experiments of MaGIXS, which include wavelength calibration, measurement of line spread function, and determination of effective area. Finally, we use the measured instrument response function to predict the expected count rates for MaGIXS flight observation looking at a typical solar active region. Title: Calibration of the MaGIXS experiment II: Flight Instrument Calibration Authors: Athiray, P. S.; Winebarger, Amy R.; Champey, Patrick; Kobayashi, Ken; Savage, Sabrina; Beabout, Brent; Beabout, Dyana; Broadway, David; Bruccoleri, Alexander R.; Cheimets, Peter; Golub, Leon; Gullikson, Eric; Haight, Harlan; Heilmann, Ralf K.; Hertz, Edward; Hogue, William; Johnson, Steven; Kegley, Jeffrey; Kolodziejczak, Jeffery; Madsen, Chad; Schattenburg, Mark L.; Siler, Richard; Vigil, Genevieve D.; Wright, Ernest Bibcode: 2021arXiv210901720A Altcode: The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a sounding rocket experiment that observes the soft X-ray spectrum of the Sun from 6.0 - 24 Angstrom (0.5 - 2.0 keV), successfully launched on 30 July 2021. End-to-end alignment of the flight instrument and calibration experiments are carried out using the X-ray and Cryogenic Facility (XRCF) at NASA Marshall Space Flight Center. In this paper, we present the calibration experiments of MaGIXS, which include wavelength calibration, measurement of line spread function, and determination of effective area. Finally, we use the measured instrument response function to predict the expected count rates for MaGIXS flight observation looking at a typical solar active region Title: Characterization of UV Bursts Using Line-Ratio Density Diagnostics Authors: Conneely, F.; Madsen, C. A.; DeLuca, E. Bibcode: 2020AGUFMSH0010005C Altcode: We compare abundance-sensitive and abundance-insensitive electron density diagnostics for a large sample of UV burst spectra. These bursts are compact (~1 arcsec), short-lived (~minutes to hours) active-region phenomena, forming in the cool lower solar atmosphere and capable of reaching nearly 100,000K. They exhibit significant intensification and broadening/splitting of the Si IV 1393.76/1402.77 Å lines, which we believe are signatures of magnetic reconnection. Bursts also display absorption from cool metallic ions Ni II and Fe II, suggesting that they form deep in the chromosphere. These unusual phenomena are critical to understanding energy and mass transfer within the solar atmosphere, possibly contributing to upper-chromospheric and coronal heating and affecting the energetics and dynamics of the lower atmosphere. We employ a semi-automated detection algorithm to assemble a sample of over 9,800 UV burst spectra for Interface Region Imaging Spectrograph (IRIS) observations of two active regions spanning several days.

We perform line-ratio density diagnostics using O IV and S IV pairs as well as a Si IV / O IV ratio. Since bursts are characterized by strong Si IV 1402.77 Å emission and O IV 1401.16 Å also appears strongly in a majority of burst spectra, the Si IV / O IV diagnostic has the potential to be a robust density indicator. There is a significant uncertainty around the use of different-species diagnostics due to their strong dependence on relative atomic abundances, which are poorly constrained in the chromosphere. We compare the Si IV / O IV diagnostic with the abundance-insensitive ratios of O IV 1399.78 Å / O IV 1401.16 Å, O IV 1401.16 Å / O IV 1404.81 Å, and S IV 1404.85 Å / S IV 1406.06 Å and comment on the viability of the Si IV /O IV method in burst regions. We also find the rates of detection for these lines in our spectra. Our density analysis provides useful constraints on UV burst formation altitudes and aids in the comparison of observations to models.

This work is supported by the NSF-REU Solar Physics program at SAO, grant number AGS-1850750 and NASA H-SR grant number 80NSSC18K1124. Title: EUV imaging and spectroscopy for improved space weather forecasting Authors: Golub, Leon; Cheimets, Peter; DeLuca, Edward E.; Madsen, Chad A.; Reeves, Katharine K.; Samra, Jenna; Savage, Sabrina; Winebarger, Amy; Bruccoleri, Alexander R. Bibcode: 2020JSWSC..10...37G Altcode: Accurate predictions of harmful space weather effects are mandatory for the protection of astronauts and other assets in space, whether in Earth or lunar orbit, in transit between solar system objects, or on the surface of other planetary bodies. Because the corona is multithermal (i.e., structured not only in space but also in temperature), wavelength-separated data provide crucial information that is not available to imaging methods that integrate over temperature. The extreme ultraviolet (EUV) wavelengths enable us to focus directly on high temperature coronal plasma associated with solar flares, coronal mass ejections (CMEs), and shocked material without being overwhelmed by intensity from the solar disk. Both wide-field imaging and spectroscopic observations of the solar corona taken from a variety of orbits (e.g., Earth, L1, or L5) using suitably-chosen EUV instrumentation offer the possibility of addressing two major goals to enhance our space weather prediction capability, namely: (1) Improve our understanding of the coronal conditions that control the opening and closing of the corona to the heliosphere and consequent solar wind streams, and (2) Improve our understanding of the physical processes that control the early evolution of CMEs and the formation of shocks, from the solar surface out into the extended corona. Title: Eclipse Results from the Airborne Infrared Spectrometer (AIR-Spec) and the Extreme-ultraviolet Imaging Spectrometer (EIS) Authors: Tañón Reyes, N.; Samra, J.; Madsen, C.; DeLuca, E. Bibcode: 2020AAS...23521009T Altcode: The Sun's dynamic outermost atmospheric layer, the corona, exhibits extremely high temperatures meaning it's in a state of hydrostatic and thermodynamic disequilibrium which leads to solar activity, such as flares and coronal mass ejections. This activity can dramatically affect humanity's infrastructure and technology in space and on Earth. Understanding the coronal magnetic field would allow for predictions of these magnetic reconnection-driven violent events. Measuring the magnetic field is possible via the study of magnetically sensitive emission lines in the infrared (IR) via the Zeeman effect. The corona emits some IR emission lines, however, the solar surface's intensity overwhelms them. To study these lines, we can observe total solar eclipses wherein the moon blocks out the surface's continuous emission. The Airborne Infrared Spectrometer (AIR-Spec) is a pathfinder for future infrared spectrometers and spectro-polarimeters that will measure the coronal magnetic field. On July 2, 2019 AIR-Spec observed the total solar eclipse over the South Pacific from onboard an aircraft. It flew at 13km to avoid low-altitude water vapor, the primary absorber of IR radiation on Earth. AIR-Spec characterized four emission lines to determine their viability for future instruments to measure the coronal magnetic field. Comparing the intensity gradients for the observed IR lines with extreme-ultraviolet (EUV) lines from the EUV Imaging Spectrometer (EIS) gives us information regarding the excitation processes in the corona, providing improvements to the atomic models. We also determine the value of the IR lines as plasma temperature and density diagnostics, using EIS data to supplement our analysis. The analysis of the temperature and density will help explain the behavior of the plasma, which will allow the mapping of the coronal magnetic field. Lastly, we discuss how AIR-Spec will continue its mission during both the 2020 and 2024 total solar eclipses as well as its influence on future spectro-polarimetric missions. This work is supported by the NSF-REU solar physics program at SAO [grant# AGS-1560313] and the NSF Airborne InfraRed Spectrograph (AIR-Spec) 2019 Eclipse Flight [award# 1822314]. Title: Total Solar Eclipse Science and Outreach in Perú Authors: Tañón Reyes, N.; Madsen, C. Bibcode: 2020AAS...23523907T Altcode: On July 2nd, 2019, the Airborne Infrared Spectrometer (AIR-Spec) observed the total solar eclipse over the South Pacific from onboard an aircraft as a pathfinder for future infrared spectrometers and spectro-polarimeters that will measure the Sun's coronal magnetic field. In addition to research, we led outreach activities in Spanish, including lectures and tours, regarding the scientific importance of studying solar eclipses for predicting solar activity. The lecture was a 45-minute talk in Spanish at the Universidad Nacional de Ingeniería (trans. National University of Engineering) in Lima, Perú. The next day, following the lecture, we spoke with the local media, embassy officials and local scientists in Spanish about our project and instrument. This meeting with journalists led to a front-page story in a local newspaper regarding our scientific study, allowing the science to reach a broad audience across the capital. Through these interactions, we learned colloquia and other research-oriented outreach events in Spanish are rare. Therefore, this information is largely inaccessible to those who are not fluent in English, stressing the need for this type of work in Spanish-speaking communities. While preparing for these events, we learned that fellow native Spanish speakers at our home institution have not given a colloquium in Spanish and were not comfortable with the idea as they do not have the vocabulary. The scientific papers and textbooks we read, even those originating from Spanish-speaking countries, are predominantly in English, and therefore the technical terms are not easily learned or found. As a result, we recognized if one does not know English, one loses the opportunity to learn about the current status of scientific research. Having this information readily available in Spanish will also allow for more people to get involved in scientific endeavors and for a better exchange of knowledge between communities. For that reason, during the eclipse in South America next year, we plan on hosting more events such as these. This work is supported by the NSF-REU solar physics program at SAO [grant# AGS-1560313] and the NSF Airborne InfraRed Spectrograph (AIR-Spec) 2019 Eclipse Flight [award# 1822314]. Title: The 2019 AIR-Spec Mission: Results from Coordinated Infrared and EUV Spectroscopic Observations of the Corona During the South Pacific Total Solar Eclipse Authors: Madsen, C. A.; Samra, J.; Tañón Reyes, N.; DeLuca, E. Bibcode: 2019AGUFMSH33A..04M Altcode: After a successful maiden voyage in 2017, The Airborne Infrared Spectrometer (AIR-Spec) embarked on another observing mission, this time targeting the July 2, 2019 total solar eclipse over the South Pacific Ocean. AIR-Spec, designed specifically for operation onboard aircraft, observes coronal infrared emission lines between 1.4 μm and 3.0 μm during total solar eclipses. It proved its viability during the August 21, 2017 total solar eclipse and underwent significant design improvements in preparation for the 2019 mission, resulting in a vastly reduced thermal background and more precise pointing control. These improvements allowed for an unprecedented view of the underexplored near-infrared corona, a wavelength regime critical to the advancement of solar physics due to the potential for direct coronal magnetic field measurements via spectrally resolved observations of the Zeeman effect. In pursuit of this goal, and with coordinated support from the Extreme-ultraviolet Imaging Spectrometer (EIS), we present the results from a number of studies involving four infrared lines detected by AIR-Spec: S XI 1.39 μm, Si X 1.43 μm, S XI 1.92 μm, and Fe IX 2.85 μm. First, we explore the effects of photoexcitation upon the Si X 1.43 μm line by comparing its spatial radiance profile to Si X lines in the EUV, further constraining atomic models of coronal emission such as CHIANTI. Next, we probe the diagnostic potential of the electron density-sensitive S XI 1.39/1.92 μm line pair while characterizing the uncertainties arising from atmospheric absorption in and around the S XI 1.39 μm line. Also, as an extension to previously published research, we take advantage of the improved sensitivity and stability of AIR-Spec to perform more precise temperature diagnostics using the emission measure (EM) loci method. Finally, we demonstrate how these results will influence future AIR-Spec missions and upcoming spectro-polarimetric instruments, including those planned for the Daniel K. Inouye Solar Telescope (DKIST) as well as a proposed balloon-based coronagraph for coronal magnetic field measurements. 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: 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: Unfolding Overlapped Slitless Imaging Spectrometer Data for Extended Sources Authors: Winebarger, Amy R.; Weber, Mark; Bethge, Christian; Downs, Cooper; Golub, Leon; DeLuca, Edward; Savage, Sabrina; del Zanna, Giulio; Samra, Jenna; Madsen, Chad; Ashraf, Afra; Carter, Courtney Bibcode: 2019ApJ...882...12W Altcode: 2018arXiv181108329W Slitless spectrometers can provide simultaneous imaging and spectral data over an extended field of view, thereby allowing rapid data acquisition for extended sources. In some instances, when the object is greatly extended or the spectral dispersion is too small, there may be locations in the focal plane where emission lines at different wavelengths contribute. It is then desirable to unfold the overlapped regions in order to isolate the contributions from the individual wavelengths. In this paper, we describe a method for such an unfolding, using an inversion technique developed for an extreme ultraviolet imaging spectrometer and coronagraph named the COronal Spectroscopic Imager in the EUV (COSIE). The COSIE spectrometer wavelength range (18.6-20.5 nm) contains a number of strong coronal emission lines and several density sensitive lines. We focus on optimizing the unfolding process to retrieve emission measure maps at constant temperature, maps of spectrally pure intensity in the Fe XII and Fe XIII lines, and density maps based on both Fe XII and Fe XIII diagnostics. Title: Coronal Plasma Characterization via Coordinated Infrared and Extreme Ultraviolet Observations of a Total Solar Eclipse Authors: Madsen, Chad A.; Samra, Jenna E.; Del Zanna, Giulio; DeLuca, Edward E. Bibcode: 2019ApJ...880..102M Altcode: 2019arXiv190110425M We present coordinated coronal observations of the 2017 August 21 total solar eclipse with the Extreme-ultraviolet Imaging Spectrometer (EIS) and the Airborne Infrared Spectrometer (AIR-Spec). These instruments provide an unprecedented view of the solar corona in two disparate wavelength regimes, the extreme ultraviolet (EUV) and the near- to mid-infrared (IR), opening new pathways for characterizing the complex coronal plasma environment. During totality, AIR-Spec sampled coronal IR spectra near the equatorial west limb, detecting strong sources of Mg VIII, S XI, Si IX, and Si X in two passbands encompassing 1.4-4 μm. We apply an intensity-ratio diagnostic to a strong resonant Fe XII line pair arising from the coordinated EIS observations. This results in a high-resolution map of electron density throughout the shared EIS/AIR-Spec field of view. Electron density measurements allow us to produce a similar map of plasma temperature using emission measure (EM) loci analysis as applied to 27 EIS emission lines, providing temperatures of 106.12 ± 103.5 K along the limb and 106.19 ± 103.5 K at about 100″ outward. Applying EM loci analysis to AIR-Spec IR spectra coadded over two 31″ wide ranges centered at two locations, 30″ and 100″ from the limb, produces temperatures consistent with the EIS data, albeit suffering from moderate uncertainties. Regardless, we demonstrate that EUV spectral data are valuable constraints to coronal IR emission models, and will be powerful supplements for future IR solar observatories, particularly DKIST. Title: Solar Ultraviolet Bursts Authors: Young, Peter R.; Tian, Hui; Peter, Hardi; Rutten, Robert J.; Nelson, Chris J.; Huang, Zhenghua; Schmieder, Brigitte; Vissers, Gregal J. M.; Toriumi, Shin; Rouppe van der Voort, Luc H. M.; Madjarska, Maria S.; Danilovic, Sanja; Berlicki, Arkadiusz; Chitta, L. P.; Cheung, Mark C. M.; Madsen, Chad; Reardon, Kevin P.; Katsukawa, Yukio; Heinzel, Petr Bibcode: 2018SSRv..214..120Y Altcode: 2018arXiv180505850Y The term "ultraviolet (UV) burst" is introduced to describe small, intense, transient brightenings in ultraviolet images of solar active regions. We inventorize their properties and provide a definition based on image sequences in transition-region lines. Coronal signatures are rare, and most bursts are associated with small-scale, canceling opposite-polarity fields in the photosphere that occur in emerging flux regions, moving magnetic features in sunspot moats, and sunspot light bridges. We also compare UV bursts with similar transition-region phenomena found previously in solar ultraviolet spectrometry and with similar phenomena at optical wavelengths, in particular Ellerman bombs. Akin to the latter, UV bursts are probably small-scale magnetic reconnection events occurring in the low atmosphere, at photospheric and/or chromospheric heights. Their intense emission in lines with optically thin formation gives unique diagnostic opportunities for studying the physics of magnetic reconnection in the low solar atmosphere. This paper is a review report from an International Space Science Institute team that met in 2016-2017. Title: Instrument Calibration of the Interface Region Imaging Spectrograph (IRIS) Mission Authors: Wülser, J. -P.; Jaeggli, S.; De Pontieu, B.; Tarbell, T.; Boerner, P.; Freeland, S.; Liu, W.; Timmons, R.; Brannon, S.; Kankelborg, C.; Madsen, C.; McKillop, S.; Prchlik, J.; Saar, S.; Schanche, N.; Testa, P.; Bryans, P.; Wiesmann, M. Bibcode: 2018SoPh..293..149W Altcode: The Interface Region Imaging Spectrograph (IRIS) is a NASA small explorer mission that provides high-resolution spectra and images of the Sun in the 133 - 141 nm and 278 - 283 nm wavelength bands. The IRIS data are archived in calibrated form and made available to the public within seven days of observing. The calibrations applied to the data include dark correction, scattered light and background correction, flat fielding, geometric distortion correction, and wavelength calibration. In addition, the IRIS team has calibrated the IRIS absolute throughput as a function of wavelength and has been tracking throughput changes over the course of the mission. As a resource for the IRIS data user, this article describes the details of these calibrations as they have evolved over the first few years of the mission. References to online documentation provide access to additional information and future updates. Title: Results of the IRIS UV Burst Survey, Part I: Active Regions Tracked Limb to Limb Authors: Madsen, C. A.; DeLuca, E. Bibcode: 2017AGUFMSH43A2802M Altcode: We present results from the first phase of an effort to thoroughly characterize UV bursts within the Interface Region Imaging Spectrograph (IRIS) data catalogue. The observational signatures of these phenomena include dramatically intensified and broadened NUV/FUV emission line profiles with absorption features from cool metallic ions. These properties suggest that UV bursts originate from plasma at transition region temperatures (≥ 80,000 K) which is deeply embedded in the cool lower chromosphere ( 5,000 K). Rigorously characterizing the energetic and dynamical properties of UV bursts is crucial since they have considerable potential to heat active region chromospheres and could provide critical constraints for models of magnetic reconnection in these regions. The survey first focuses on IRIS observations of active regions tracked from limb to limb. All observations consist of large field-of-view raster scans of 320 or 400 steps each, which allow for widespread detection of many burst profiles at the expense of having limited short-term time evolution information. We detect bursts efficiently by applying a semi-automated single-Gaussian fitting technique to Si IV 1393.8 Å emission profiles that isolates the distinct burst population in a 4-D parameter space. The robust sample of NUV/FUV burst spectra allows for precise constraints of properties critical for modeling reconnection in the chromosphere, including outflow kinetic energy, density estimates from intensity ratios of Si IV 1402.8 Å and O IV 1401.2 Å emission lines, and coincident measures of emission in other wavelengths. We also track burst properties throughout the lifetimes of their host active regions, noting changes in detection rate and preferential location as the active regions evolve. Finally, the tracked active region observations provide a unique opportunity to investigate line-of-sight effects on observed UV burst spectral properties, particularly the strength of Ni II 1393.3 Å absorption, a feature that may be important in identifying the upward conduction of burst thermal energy through the chromosphere. Title: Exploring the Time Evolution of Cool Metallic Absorption Features in UV Burst Spectra Authors: Belmes, K.; Madsen, C. A.; DeLuca, E. Bibcode: 2017AGUFMSH51C2499B Altcode: UV bursts are compact brightenings in active regions that appear in UV images. They are identified through three spectroscopic features: (1) broadening and intensification of NUV/FUV emission lines, (2) the presence of optically thin Si IV emission, and (3) the presence of absorption features from cool metallic ions. Properties (2) and (3) imply that bursts exist at transition region temperatures (≥ 80,000 K) but are located in the cooler lower chromosphere ( 5,000 K). Their energetic and dynamical properties remain poorly constrained. Improving our understanding of this phenomena could help us further constrain the energetic and dynamical properties of the chromosphere, as well as give us insight into whether or not UV bursts contribute to chromospheric and/or coronal heating. We analyzed the time evolution of UV bursts using spectral data from the Interface Region Imaging Spectrograph (IRIS). We inspected Si IV 1393.8 Å line profiles for Ni II 1393.3 Å absorption features to look for signs of heating. Weakening of absorption features over time could indicate heating of the cool ions above the burst, implying that thermal energy from the burst could rapidly conduct upward through the chromosphere. To detect the spectral profiles corresponding to bursts, we applied a four-parameter Gaussian fit to every profile in each observation and took cuts in parameter space to isolate the bursts. We then manually reviewed the remaining profiles by looking for a statistically significant appearance of Ni II 1393.3 Å absorption. We quantified these absorption features by normalizing the Si IV 1393.8 Å emission profiles and measuring the maximum fractional extinction in each. Our preliminary results indicate that Ni II 1393.3 Å absorption may undergo a cycle of strengthening and weakening throughout a burst's lifetime. However, further investigation is needed for confirmation. This work is supported by the NSF-REU solar physics program at SAO, grant number AGS-1560313. 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: Waves, Bursts, and Instabilities: A Multi-Scale Investigation of Energetic Plasma Processes in the Solar Chromosphere and Transition Region Authors: Madsen, Chad Allen Bibcode: 2017PhDT.......264M Altcode: The chromosphere and transition region of the solar atmosphere provide an interface between the cool photosphere ( 6000 K) and the hot corona ( 1 million K). Both layers exhibit dramatic deviations from thermal and hydrostatic equilibrium in the form of intense plasma heating and mass transfer. The exact mechanisms responsible for transporting energy to the upper atmosphere remain unknown, but these must include a variety of energetic processes operating across many spatial and temporal scales. This dissertation comprises three studies of possible mechanisms for plasma heating and energy transport in the solar chromosphere and transition region. The first study establishes the theoretical framework for a collisional, two-stream plasma instability in the quiet-Sun chromosphere similar to the Farley-Buneman instability which actively heats the E-region of Earth's ionosphere. After deriving a linear dispersion relationship and employing a semi-empirical model of the chromosphere along with carefully computed collision frequencies, this analysis shows that the threshold electron drift velocity for triggering the instability is remarkably low near the temperature minimum where convective overshoots could continuously trigger the instability. The second study investigates simultaneous Interface Region Imaging Spectrograph (IRIS) observations of magnetohydrodynamic (MHD) waves in the chromospheres and transition regions of sunspots. By measuring the dominant wave periods, apparent phase velocities, and spatial and temporal separations between appearances of two observationally distinct oscillatory phenomena, the data show that these are consistent with upward-propagating slow magnetoacoustic modes tied to inclined magnetic field lines in the sunspot, providing a conduit for photospheric seismic energy to transfer upward. The third and final study focuses on intense, small-scale ( 1 arcsec) active region brightenings known as IRIS UV bursts. These exhibit dramatic FUV/NUV emission line splitting and deep absorption features, suggesting that they result from reconnection events embedded deep in the cool lower chromosphere. IRIS FUV spectral observations and Solar Dynamics Obser- vatory/Helioseismic and Magnetic Imager (SDO/HMI) magnetograms of a single evolving active region reveal that bursts prefer to form during the active region's emerging phase. These bursts tend to be spatially coincident with small-scale, photospheric, bipolar regions of upward and downward magnetic flux that dissipate as the active region matures. Title: Initial Results of a Large-scale Statistical Survey of Small-scale UV Bursts with IRIS and SDO Authors: Madsen, C. A.; DeLuca, E. Bibcode: 2016AGUFMSH31B2570M Altcode: UV bursts are small-scale ( 1 arcsec or less) brightenings observed in the NUV/FUV passbands of the Interface Region Imaging Spectrograph (IRIS). These peculiar phenomena are found exclusively in active regions and exhibit dramatic and defining spectroscopic characteristics. In particular, they present intense broadening and splitting, often in excess of 70 km s-1, in all bright emission lines observable by IRIS. Furthermore, these broadened lines also display strong absorption from cool metallic ions such as Fe II and Ni II which typically populate the chromosphere. These features suggest that bursts are bidirectional plasma flows at transition region temperatures embedded much farther down in the cool chromosphere. To better characterize these phenomena, we have launched a statistical survey encompassing the entire IRIS data catalogue to date and its accompanying data from the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI). We sample a wide variety of IRIS observations of Si IV lines, ranging from large 400-step rasters for large detection rates to short-cadence sit-and-stare observations to provide in-depth time evolution data of individual bursts. Detection is streamlined by a semi-automated method that isolates characteristic burst spectra based on single-Gaussian fit parameters, greatly reducing search times in the vast IRIS catalogue. Our initial results demonstrate that UV bursts tend to appear when active regions are young and actively emerging, preferring to populate poorly developed inversion lines composed of numerous small mixed-polarity regions. Burst occurrence rates peak at 30-70 per hour in young active regions, decreasing as those regions age. We also find dramatic variations in spectral morphology in spatial scans of bursts with many split into distinct, opposing, resolved regions of blueshifts and redshifts. Finally, we find little evidence for coronal counterparts in AIA 171 Å, but we do find that a significant ratio of bursts coincide with localized bright features in AIA 1700 Å, lending support to the link between bursts and Ellerman bombs. With further involvement in the survey, we hope to constrain the burst/Ellerman bomb coincidence, the time evolution of burst spectral morphologies, and the distribution of their peak kinetic energies. Title: Tracking Sunspot Waves Across the Solar Disk using IRIS Authors: Sager, H. A.; Madsen, C. A.; DeLuca, E. Bibcode: 2016AGUFMSH21E2568S Altcode: Waves can be observed in the transition region and upper chromosphere of sunspots. Two particular phenomena, running waves and umbral flashes, can be seen in the 1400 Å and 2796 Å bandpasses, respectively, on slit-jaw images from the Interface Region Imaging Spectrograph (IRIS). How running waves propagate through the solar atmosphere is still a topic of debate revolving around two theories. The trans-sunspot theory explains that these waves propagate radially across the sunspot from its center just as they appear visually. The upward propagating theory illustrates that these waves are tied to the magnetic field lines and are therefore slow magnetoacoustic waves, indicating that the observed apparent motion of the waves is not real. Previous studies focused on individual observations at a fixed viewing angle, leaving the results susceptible to line-of-sight bias. To test for this bias, we observed the leading sunspots of AR 11836 and AR 12546 as they traveled from the disk center to the western limb. To assess the two theories, we applied global wavelet analysis to our high-pass filtered slit-jaw images and were able to find the spatial distribution of dominate wave periods for both phenomena. We then compared the period distribution to magnetic field line inclinations from the Helioseismic and Magnetic Imager (HMI). From this, we find a clear correlation between magnetic field line inclination and wave period as both increase outward from the sunspot center. The period increases from 180 s from the sunspot center to 240 s near the edge of the penumbra for all of our viewing angles, nullifying the existence of a line-of-sight bias and lending credence to the upward propagating theory. The importance of discovering how these waves are moving through the solar atmosphere could provide a mechanism for transporting local seismic energy from the photosphere to the corona. Title: Are IRIS Bombs Connected to Ellerman Bombs? Authors: Tian, Hui; Xu, Zhi; He, Jiansen; Madsen, Chad Bibcode: 2016ApJ...824...96T Altcode: 2016arXiv160405423T Recent observations by the Interface Region Imaging Spectrograph (IRIS) have revealed pockets of hot gas (∼2-8 × 104 K) potentially resulting from magnetic reconnection in the partially ionized lower solar atmosphere (IRIS bombs; IBs). Using joint observations between IRIS and the Chinese New Vacuum Solar Telescope, we have identified 10 IBs. We find that 3 are unambiguously and 3 others are possibly connected to Ellerman bombs (EBs), which show intense brightening of the extended {{{H}}}α wings without leaving an obvious signature in the {{{H}}}α core. These bombs generally reveal the following distinct properties: (1) the O IV 1401.156 Å and 1399.774 Å lines are absent or very weak; (2) the Mn I 2795.640 Å line manifests as an absorption feature superimposed on the greatly enhanced Mg II k line wing; (3) the Mg II k and h lines show intense brightening in the wings and no dramatic enhancement in the cores; (4) chromospheric absorption lines such as Ni II 1393.330 Å and 1335.203 Å are very strong; and (5) the 1700 Å images obtained with the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory reveal intense and compact brightenings. These properties support the formation of these bombs in the photosphere, demonstrating that EBs can be heated much more efficiently than previously thought. We also demonstrate that the Mg II k and h lines can be used to investigate EBs similarly to {{{H}}}α , which opens a promising new window for EB studies. The remaining four IBs obviously have no connection to EBs and they do not have the properties mentioned above, suggesting a higher formation layer, possibly in the chromosphere. Title: Observations of Small-scale IRIS Bombs (Reconnection Events) in an Evolving Active Region Authors: Madsen, C. A.; Tian, H.; DeLuca, E. E. Bibcode: 2015AGUFMSH31B2414M Altcode: We present the first Interface Region Imaging Spectrograph (IRIS) observations of small-scale bombs evolving with their host active region. Bombs appear most clearly in the IRIS 1330 Å and 1400 Å slit-jaw images as small (~1 arcsec), compact, intense brightenings at transition region temperatures. Their NUV/FUV emission spectra exhibit dramatic line splitting and strong absorption features indicative of bidirectional flows from magnetic reconnection embedded deep within the cool lower solar atmosphere. The bombs may contribute significantly to the heating of the solar atmosphere in active regions; however, it's unclear how prevalent the bombs are throughout the lifetime of an active region. Using a semi-automated detection method, we locate bombs within AR 11850 over the course of four observations from 06:00 UT on September 25, 2013 until 11:30 UT the next day. The active region is first observed in an emerging phase and rapidly grows into a mature active region with well-developed sunspots. The bomb occurrence rate drops dramatically as the active region fully emerges. We also find that the bombs fall into two distinct populations: one appears largely during active region emergence and contains a majority of the bombs, while the other population is present regardless of active region age. The first population of bombs is typically found embedded in the low-lying loops prominent in the young active region. Furthermore, we use Solar Dynamics Observatory/Helioseismic and Magnetic Imager (SDO/HMI) line-of-sight magnetograms to show that the bombs associated with the first population occur at the boundaries between the upward and downward flux of small, isolated bipolar regions. These regions dissipate as the active region emerges and reconfigures its magnetic field into two large network patches of upward and downward flux with a clear inversion line. The second, smaller population of bombs usually occurs far from the active region loop structures in the plage and sunspot penumbrae. They are associated with the boundaries between strong upward or downward flux and regions where the magnetic field is perpendicular to the line of sight. Title: Observations of Umbral Flashes and Running Sunspot Waves with the Interface Region Imaging Spectrograph Authors: Madsen, Chad A.; Tian, Hui; DeLuca, Edward E. Bibcode: 2015ApJ...800..129M Altcode: We present simultaneous, high-resolution, multi-temperature observations of running waves and umbral flashes in a sunspot with the Interface Region Imaging Spectrograph. We analyze intensity variations in slit-jaw images to investigate the relationship between running waves in the 1400 Å (Si IV/transition region) passband and umbral flashes in the 2796 Å (Mg II/chromosphere) passband. Using global wavelet analysis, we find that the dominant wave periods increase from approximately 150 s near the sunspot center to about 300 s in the penumbra in both passbands. This coincides extremely well with the radially increasing inclination of magnetic field lines observed with Solar Dynamics Observatory/Helioseismic and Magnetic Imager, suggesting that the waves are propagating vertically along the inclined field lines. Furthermore, apparent horizontal velocities for running waves decrease from about 12 km s-1 in the umbra to about 4 km s-1 in the penumbra which is predicted by the same inclined field geometry. Finally, we find that umbral flashes lead running waves in both the spatial and temporal domains. The former result is attributable to the inclined field geometry; however, the geometry does not predict the radially increasing time lag which is likely due to the opacity difference between the emission lines that dominate the two passbands. These results suggest that running waves and umbral flashes both originate from photospheric p-mode oscillations and are manifestations of upward-propagating slow magnetoacoustic modes at different altitudes and temperatures. The apparent trans-sunspot propagation of running waves is not real but rather an image of these upward-propagating modes traveling along field lines of radially increasing inclination. Title: Jorge Melnick Retires from ESO Authors: Madsen, C. Bibcode: 2014Msngr.158...59M Altcode: No abstract at ADS Title: First Simulations of a Collisional Two-Stream Instability in the Chromosphere Authors: Oppenheim, Meers; Dimant, Yakov; Madsen, Chad Allen; Fontenla, Juan Bibcode: 2014AAS...22430205O Altcode: Observations and modeling shows that immediately above the temperature minimum in the solar atmosphere, a steep rise from below 4,000 K to over 6,000K occurs. Recent papers show that a collisional two-stream plasma instability called the Farley-Buneman Instability can develop at the altitudes where this increase occurs. This instability may play an important role in transferring energy from turbulent neutral flows originating in the photosphere to the mid-chromosphere in the form of heat. Plasma turbulence resulting from this instability could account for some or most of this intense chromospheric heating. This paper presents a set of simulations showing the development and evolution of the Farley-Buneman Instability (FBI) applicable to the chromosphere. It compares these results with the better-understood ionospheric FBI. It examines the linear behavior and the dependence of growth rates for a range of altitudes and driving flows. It also presents the first study of FBI driven plasma nonlinearities and turbulence in the chromosphere. This research should help us evaluate the FBI as a mechanism to convert neutral flow and turbulence energy into electron thermal energy in the quiet Sun. Title: Theory of Collisional Two-Stream Plasma Instabilities in the Solar Chromosphere Authors: Madsen, Chad Allen; Dimant, Yakov; Oppenheim, Meers; Fontenla, Juan Bibcode: 2014AAS...22432303M Altcode: The solar chromosphere experiences intense heating just above its temperature minimum. The heating increases the electron temperature in this region by over 2000 K. Furthermore, it exhibits little time variation and appears widespread across the solar disk. Although semi-empirical models, UV continuum observations, and line emission measurements confirm the existence of the heating, its source remains unexplained. Potential heating sources such as acoustic shocks, resistive dissipation, and magnetic reconnection via nanoflares fail to account for the intensity, persistence, and ubiquity of the heating. Fontenla (2005) suggested turbulence from a collisional two-stream plasma instability known as the Farley-Buneman instability (FBI) could contribute significantly to the heating. This instability is known to heat the plasma of the E-region ionosphere which bears many similarities to the chromospheric plasma. However, the ionospheric theory of the FBI does not account for the diverse ion species found in the solar chromosphere. This work develops a new collisional, two-stream instability theory appropriate for the chromospheric plasma environment using a linear fluid analysis to derive a new dispersion relationship and critical E x B drift velocity required to trigger the instability. Using a 1D, non-local thermodynamic equilibrium, radiative transfer model and careful estimates of collision rates and magnetic field strengths, we calculate the trigger velocities necessary to induce the instability throughout the chromosphere. Trigger velocities as low as 4 km s^-1 are found near the temperature minimum, well below the local neutral acoustic speed in that region. From this, we expect the instability to occur frequently, converting kinetic energy contained in neutral convective flows from the photosphere into thermal energy via turbulence. This could contribute significantly to chromospheric heating and explain its persistent and ubiquitous nature. Title: The Multi-species Farley-Buneman Instability in the Solar Chromosphere Authors: Madsen, Chad A.; Dimant, Yakov S.; Oppenheim, Meers M.; Fontenla, Juan M. Bibcode: 2014ApJ...783..128M Altcode: 2013arXiv1308.0305M Empirical models of the solar chromosphere show intense electron heating immediately above its temperature minimum. Mechanisms such as resistive dissipation and shock waves appear insufficient to account for the persistence and uniformity of this heating as inferred from both UV lines and continuum measurements. This paper further develops the theory of the Farley-Buneman instability (FBI) which could contribute substantially to this heating. It expands upon the single-ion theory presented by Fontenla by developing a multiple-ion-species approach that better models the diverse, metal-dominated ion plasma of the solar chromosphere. This analysis generates a linear dispersion relationship that predicts the critical electron drift velocity needed to trigger the instability. Using careful estimates of collision frequencies and a one-dimensional, semi-empirical model of the chromosphere, this new theory predicts that the instability may be triggered by velocities as low as 4 km s-1, well below the neutral acoustic speed. In the Earth's ionosphere, the FBI occurs frequently in situations where the instability trigger speed significantly exceeds the neutral acoustic speed. From this, we expect neutral flows rising from the photosphere to have enough energy to easily create electric fields and electron Hall drifts with sufficient amplitude to make the FBI common in the chromosphere. If so, this process will provide a mechanism to convert neutral flow and turbulence energy into electron thermal energy in the quiet Sun. Title: Retirement of Massimo Tarenghi Authors: Madsen, C. Bibcode: 2013Msngr.153...39M Altcode: Massimo Tarenghi, chronologically MPG/ESO project scientist, NTT project manager, VLT programme manager and first Director, ALMA Director and ESO Representative in Chile, has retired after 35 years at ESO. A brief summary of his achievements is presented. Title: Presenting the ESO Story: One Hundred and Fifty Messengers Authors: Madsen, C. Bibcode: 2012Msngr.150...74M Altcode: Since 1974, The ESO Messenger has been one of ESO's primary communication channels to the outside world in particular. It has provided a window not only onto the organisation, its projects and people, but also onto the research carried out by ESO's ever-growing user community. Last but not least, today it constitutes a fascinating historical source, documenting the life and evolution of ESO over the last 38 years. Title: Large-Scale Intrinsic Alignments of Galaxies Authors: Brainerd, Tereasa G.; Agustsson, I.; Madsen, C. A.; Edmonds, J. A. Bibcode: 2010AAS...21540906B Altcode: 2010BAAS...42..234B We compute the two-point image correlation function for bright galaxies in the seventh data release of the Sloan Digital Sky Survey (SDSS) over angular scales 0.01 arcmin to 120 arcmin and projected separations 0.01 Mpc to 10 Mpc. We restrict our analysis to SDSS galaxies with spectroscopic redshifts and we find strong evidence for intrinsic alignment of the galaxy images. On scales greater than 40 kpc, the intrinsic alignment of the SDSS galaxy images compares well with the intrinsic alignment of galaxy images in a LCDM universe, provided we impose Gaussian-random errors on the position angles of the theoretical galaxies with a dispersion of 25 degrees. Without the inclusion of these errors, the amplitude of the two-point image correlation function for the theoretical galaxies is a factor of 2 higher than it is for the SDSS galaxies. We interpret this as a combination of modest position angle errors for the SDSS galaxies, as well as a need for modest misalignment of mass and light in the theoretical galaxies. The intrinsic alignment of the SDSS galaxies shows no dependence on the specific star formation rates of the galaxies and, at most, a very weak dependence on the colors and stellar masses of the galaxies. At the 3 sigma level, however, we find an indication that the images of the most luminous SDSS galaxies are more strongly aligned with each other than are the images of the least luminous SDSS galaxies. This work was supported by NSF grant AST-0708468. Title: Large-Scale Intrinsic Alignment of Galaxy Images Authors: Brainerd, Tereasa G.; Agustsson, Ingolfur; Madsen, Chad A.; Edmonds, Jeffrey A. Bibcode: 2009arXiv0904.3095B Altcode: We compute the two-point image correlation function for bright galaxies in the seventh data release of the Sloan Digital Sky Survey (SDSS) over angular scales 0.01' <= \theta <= 120' and projected separations 0.01 Mpc <= r <= 10 Mpc. We restrict our analysis to SDSS galaxies with accurate spectroscopic redshifts, and we find strong evidence for intrinsic alignment of the galaxy images. On scales greater than r ~ 40 kpc, the intrinsic alignment of the SDSS galaxy images compares well with the intrinsic alignment of galaxy images in a Lambda-CDM universe, provided we impose Gaussian-random errors on the position angles of the theoretical galaxies with a dispersion of 25 degrees. Without the inclusion of these errors, the amplitude of the two-point image correlation function for the theoretical galaxies is a factor of ~2 higher than it is for the SDSS galaxies. We interpret this as a combination of modest position angle errors for the SDSS galaxies, as well as a need for modest misalignment of mass and light in the theoretical galaxies. The intrinsic alignment of the SDSS galaxies shows no dependence on the specific star formation rates of the galaxies and, at most, a very weak dependence on the colors and stellar masses of the galaxies. At the ~3-sigma level, however, we find an indication that the images of the most luminous SDSS galaxies are more strongly aligned with each other than are the images of the least luminous SDSS galaxies. Title: ASTRONET: Public Outreach Authors: Ros, R. M.; Fosbury, R.; Christensen, L. L.; Del Toro Iniesta, J. C.; Fucili, L.; Hill, R.; Lorenzen, D.; Madsen, C.; Newsam, A.; Pickwick, A.; Radeva, V. Bibcode: 2009CAPJ....5...26R Altcode: We have all seen the spectacular images that the Hubble Space Telescope and other such observatories have revealed to the world. Their haunting splendour inspires and compels us as artists. But how can we capture the elusive essence of space in our own work? Title: ESO Education and Public Outreach for IYA2009 Authors: Pierce-Price, D.; Madsen, C.; Boffin, H. J.; Argandoña, G. Bibcode: 2008ca07.conf..274P Altcode: ESO, the European Organisation for Astronomical Research in the Southern Hemisphere, is planning a range of education and public outreach activities for the International Year of Astronomy 2009 (IYA2009). In addition to support for IYA2009 global Cornerstone Projects, these will include local, national, and international activities, aimed at the general public, the interested public, and school students. Title: ESO at the AAS, the AAAS and in Dublin Authors: Boffin, H.; Madsen, C. Bibcode: 2007Msngr.127...69B Altcode: The great variety of new distribution meth-ods and tools available does not replace face-to-face communication, which re-mains a most valuable activity in presenting ESO and its future needs. Face-to-face communication, in turn, takes many forms ranging from formal lectures and speeches, through less formal and infor-mal meetings and briefings, e.g. with de-cision makers or media representatives, to information stands at fairs and confer-ences. Information stands often provide a physical basis for important personal encounters. In 2006, ESO's Public Affairs Department organised or participated in more than 20 events, involving exhibitions, briefings and VIP visits. This con-stitutes a marked increase over the pre-vious years, on the one hand reflecting the growing importance and visibility of ESO, and, on the other hand, a necessity, given the need to enlist wide support for ESO's ambitious future projects. Title: Open House at the ESO Headquarters Authors: Madsen, C. Bibcode: 2006Msngr.126...50M Altcode: 2006Msngr.126f..50M On 15 October, the ESO Headquarters opened its doors to the public as part of the All-Campus Open House organised in connection with the inauguration of the extension of the underground line U6 from Munich to the Garching campus. The day was blessed with clear skies and plenty of sunshine, and a large number of citizens took advantage of the opportunity to visit the campus. The estimated number of visitors at ESO was close to 3000 people, a record number. Another record was set by the number of ESO staff who, in anticipation of the high num-ber of guests, volunteered to spend their Sunday at work to explain what ESO is doing and why it is important. Title: Universe Awareness For Young Children Authors: Scorza, C.; Miley, G.; Ödman, C.; Madsen, C. Bibcode: 2006IAUSS...2E..39S Altcode: Universe Awareness (UNAWE) is an international programme that will expose economically disadvantaged young children aged between 4 and 10 years to the inspirational aspects of modern astronomy. The programme is motivated by the premise that access to simple knowledge about the Universe is a basic birth right of everybody. These formative ages are crucial in the development of a human value system. This is also the age range in which children can learn to develop a 'feeling' for the vastness of the Universe. Exposing young children to such material is likely to broaden their minds and stimulate their world-view. The goals of Universe Awareness are in accordance with two of the United Nations Millennium goals, endorsed by all 191 UN member states, namely (i) the achievement of universal primary education and (ii) the promotion of gender equality in schools. We propose to commence Universe Awareness with a pilot project that will target disadvantaged regions in about 4 European countries (possibly Spain, France, Germany and The Netherlands) and several non-EU countries (possibly Chile, Colombia, India, Tunisia, South Africa and Venezuela). There will be two distinct elements in the development of the UNAWE program: (i) Creation and production of suitable UNAWE material and delivery techniques, (ii) Training of educators who will coordinate UNAWE in each of the target countries. In addition to the programme, an international network of astronomy outreach will be organised. We present the first results of a pilot project developed in Venezuela, where 670 children from different social environments, their teachers and members of an indigenous tribe called Ye´kuana from the Amazon region took part in a wonderful astronomical and cultural exchange that is now being promoted by the Venezuelan ministry of Education at the national level. Title: ESO's Astronomy Education Programme Authors: Pierce-Price, D. P. I.; Boffin, H.; Madsen, C. Bibcode: 2006IAUSS...2E..23P Altcode: ESO, the European Organisation for Astronomical Research in the Southern Hemisphere, has operated a programme of astronomy education for some years, with a dedicated Educational Office established in 2001. We organise a range of activities, which we will highlight and discuss in this presentation. Many are run in collaboration with the European Association for Astronomy Education (EAAE), such as the "Catch a Star!" competition for schools, now in its fourth year. A new endeavour is the ALMA Interdisciplinary Teaching Project (ITP). In conjunction with the EAAE, we are creating a set of interdisciplinary teaching materials based around the Atacama Large Millimeter Array project. The unprecedented astronomical observations planned with ALMA, as well as the uniqueness of its site high in the Atacama Desert, offer excellent opportunities for interdisciplinary teaching that also encompass physics, engineering, earth sciences, life sciences, and culture. Another ongoing project in which ESO takes part is the "Science on Stage" European science education festival, organised by the EIROforum - the group of seven major European Intergovernmental Research Organisations, of which ESO is a member. This is part of the European Science Teaching Initiative, along with Science in School, a newly-launched European journal for science educators. Overviews of these projects will be given, including results and lessons learnt. We will also discuss possibilities for a future European Astronomy Day project, as a new initiative for European-wide public education. Title: Walloon Space Days Authors: Madsen, C. Bibcode: 2006Msngr.124...42M Altcode: On 28-29 March, the Cluster Wallonie Espace, mainly a partnership of companies in the Walloon ‘Space Valley', or-ganised the first so-called ‘W Space Days' at the Colonster Castle, located on the premises of the University of Liège. The primary aim of these days is to encourage meetings between professionals in the sector and to identify new scientific and technological opportunities. They should also help to raise awareness of the activities of the space sector amongst the general public and young people in particular. Indeed the event successfully brought together scientists, industrialists, funding agencies and policymakers. On the first day, some 210 representatives of research centres, industries and organisations from 13 countries in Europe participated in the professional event, while the next day was a ‘public day'. The first morning's programme comprised a series of talks, including ELT presentations by Roberto Gilmozzi and Philippe Dierickx. Title: Finnish Parliamentary Committee at ESO Headquarters Authors: Madsen, C. Bibcode: 2006Msngr.124...38M Altcode: Finnish Parliamentary Committee at ESO Headquarters Title: ESO at AAAS Authors: Madsen, C. Bibcode: 2006Msngr.123...61M Altcode: No abstract at ADS Title: Universe Awareness . An inspirational programme for economically disadvantaged young children. Authors: Ödman, C. J.; Scorza, C.; Miley, G. K.; Madsen, C. Bibcode: 2006MmSAI..77.1014O Altcode: The beauty of the sky and its connection with the human development have inspired generations with wonder. Astronomy conveys the excitement of science to the public. Considerable resources are devoted to outreach in developed countries, with spectacular images produced by modern astronomical facilities and astronomical discoveries that change our views of the Universe.

Universe Awareness (UNAWE) is a programme for children between 4 and 10 years old. The formative ages of 4 to 10 years are crucial in child development. Children of that age can appreciate the beauty of astronomical objects and develop a ``feeling'' for the vastness of the Universe. Exposing young children to such material is likely to broaden their minds and stimulate their world-view. The programme concentrates on economically disadvantaged young children because most other children will be exposed to some knowledge about the Universe and disparities between advantaged and disadvantaged children increase with age. Venezuela hosted a successful pilot project in 2006. From spontaneous observation of the sky to a teacher-training workshop in the "Centro de Investigaciones de Astronomía" in Mérida, this was a wonderful experience for participants and organisers alike. This shows how successful the UNAWE programme can be. Title: ESO at Cer 2005 Authors: Madsen, C. Bibcode: 2005Msngr.122...48M Altcode: On November 14-15, the Brussels Exhibition Centre (Heysel) was the home of a major international conference on science communication with the title “Communicating European Research” (CER 2005). Title: Science on Stage 2005 Authors: Pierce-Price, D.; Boffin, H.; Madsen, C. Bibcode: 2005Msngr.122...47P Altcode: “Science on Stage”, the European Science Teaching Festival, is a major educational outreach programme for science teachers. It aims to identify and foster innovation within formal science education by means of exchange of best practice, workshops and seminars involving educators from all over Europe. Title: Universe Awareness for Young Children Authors: Miley, G.; Madsen, C.; Scorza de Appl, C. Bibcode: 2005Msngr.121...66M Altcode: Universe Awareness (UNA) is an international programme that will expose economically-disadvantaged young children, between ages 4 and 10 years, in developed and developing countries to the inspirational aspects of modern astronomy. Title: Towards a Europe of Knowledge and Innovation? Authors: Madsen, C. Bibcode: 2005Msngr.120...46M Altcode: THE EUROPEAN SOCIETIES ARE undergoing fast changes these years. The need to manage the European integration process as well as to develop adequate solutions in the face of globalization and the pressure on the ‘European way of life' led the Heads of states and governments of the EU to set for themselves the goal of developing the most dynamic knowledge-based economy in the world within a 10-year period. Both the goals and the policies to reach them are known as the Lisbon Agenda and the Lisbon Process, respectively, reminding us that it was in the city of Lisbon - in the year 2000 - that this development was started. Now, at half-time, the process has been reviewed and the governments have acknowledged the need to focus on the most essential policy areas that must be developed to achieve success. Title: Richard West retires Authors: Madsen, C. Bibcode: 2005Msngr.120...56M Altcode: It is hard to believe, but after 35 years of service, Richard West has retired from ESO. Born 1941 in Copenhagen, Richard did his baccalaureate in 1959. In 1964, he obtained his degree (Mag. scient. et cand. mag.) in astronomy and astrophysics at Copenhagen University, followed by a period as Assistant Professor (Amanuensis) at Copenhagen University Observatory. In 1970, he joined ESO as Assistant Astronomer to the ESO Director General, Adriaan Blaauw. Title: ESO Presentation in Copenhagen Authors: Madsen, C.; D'Odorico, S. Bibcode: 2004Msngr.118...71M Altcode: On November 8, ESO continued its series of presentations in memberstates with an event in Copenhagen. So far events have been organised in Belgium, Finland, Portugal, Sweden, Switzerland and the United Kingdom. The purpose of these presentations is to raise the awareness of ESO amongst decision-makers, academia and the media. Over time, the scope and specific focus of the national events have varied, considering the particular circumstances and the wishes of the national hosts, and accordingly, the presentation in Denmark was primarily oriented towards industry. The meeting was initiated by the Royal Danish Consulate General in Munich in conjunction with the Confederation of Danish Industries and the Ministry for Science, Technology and Innovation. Leading up to the meeting, several articles about ESO had appeared in the Danish press and the 2nd TV Channel featured a report on the ESO projects also in connection with the event. Title: Report on the EuroScience Open Forum 2004 Authors: Madsen, C. Bibcode: 2004Msngr.117...66M Altcode: SCIENCE reigned supreme in Stockholm for a period of four days in late August this year, as some 1800 scientists, administrators, policy-makers and media representatives from 68 countries convened at the EUROSCIENCE Open Forum, the first pan- European inter- and transdisciplinary science meeting on our Continent. Title: Serving European Science: The EIROforum Collaboration Authors: Madsen, C. Bibcode: 2004Msngr.116...42M Altcode: OVER THE LAST FEW years, the idea of a “European Research Area” (ERA) has gained strong support among science policy makers and, increasingly, among scientists themselves. The goal of the ERA is to establish a single “market” for research on our continent, allowing for better co-ordination of research efforts, synergies between projects, the achievement of “critical mass” (both human and financial) and thus to strengthen the competitiveness of European research. These goals necessitate deep structural changes in the way science is organised, breaking up existing borderlines and barriers between national research systems in Europe. Title: Visit EIROFORUM at ESOF 2004 Authors: Madsen, C. Bibcode: 2004Msngr.116...48M Altcode: The EuroScience Open Forum (ESOF2004) is the first pan-European interdisciplinary scientific conference, modelled on the well-known and highly successful meetings in the US by the American Association for the Advancement of Science (AAAS). ESOF2004 will be held at the Stockholm City Conference Centre in Stockholm, Sweden, this summer, between 25-28 August. It is intended to continue with ESOF meetings on a biannual basis in the future. Title: Astronomy and Space Science in the European Print Media Authors: Madsen, C. Bibcode: 2003ASSL..290...67M Altcode: 2003asco.book...67M No abstract at ADS Title: Astronomy Communication Authors: Heck, A.; Madsen, C. Bibcode: 2003ASSL..290.....H Altcode: 2003asco.book.....H Astronomers communicate all the time, with colleagues of course, but also with managers and administrators, with decision makers and takers, with social representatives, with the news media, and with the society at large. Education is naturally part of the process. Astronomy communication must take into account several specificities: the astronomy community is rather compact and well organized world-wide; astronomy has penetrated the general public remarkably well with an extensive network of associations and organizations of aficionados all over the world. Also, as a result of the huge amount of data accumulated and by necessity for their extensive international collaborations, astronomers have pioneered the development of distributed resources, electronic communications and networks coupled to advanced methodologies and technologies, often much before they become of common world-wide usage. This book is filling up a gap in the astronomy-related literature by providing a set of chapters not only of direct interest to astronomy communication, but also well beyond it. The experts contributing to this book have done their best to write in a way understandable to readers not necessarily hyperspecialized in astronomy nor in communication techniques while providing specific detailed information, as well as plenty of pointers and bibliographic elements. This book will be very useful for researchers, teachers, editors, publishers, librarians, computer scientists, sociologists of science, research planners and strategists, project managers, public-relations officers, plus those in charge of astronomy-related organizations, as well as for students aiming at a career in astronomy or related space science.

Link: http://www.wkap.nl/prod/b/1-4020-1345-0 Title: Public Communication of Astronomy Authors: Madsen, C.; West, R. M. Bibcode: 2003ASSL..290....3M Altcode: 2003asco.book....3M No abstract at ADS Title: Breaking the ground for the European research area - The conference "European research 2002" Authors: Madsen, C. Bibcode: 2002Msngr.110...46M Altcode: In the days November 11-13, about 9000 scientists, science administrators and policy makers gathered in Brussels to attend the Launch Conference for the ‘6th Framework Programme of the European Community for research, technological development and demonstration activities' - or for short, ‘FP-6'. While most participants came from the member states of the European Union, candidate countries and associated states, the meeting was in fact attended by people from 65 countries, demonstrating the wide scope and the importance of the process set in motion to create the European Research Area. Some 50 TV teams and 230 journalists from the print media covered the event, which El País, the leading Spanish newspaper, described as ‘The Science Summit in Brussels'. The strong media interest bears witness to the fact that science and technology (and with them, also education) are playing an increasingly important and visible role in the public sphere and that the organization and execution of research, as well as the exploitation of scientific results, are assuming importance in the mainstream political debate. Title: Celebrating ESO's 40th anniversary Authors: Madsen, C. Bibcode: 2002Msngr.110...45M Altcode: ESO has always been a forwardlooking organization, focussed on present and future programmes and projects. In its 40th year, this is as true as ever, as ESO keeps its eyes on implementing the VLTI, initiating the development of the second-generation instrumentation for the VLT and, of course, embarking on Phase II of the ALMA project, for which the ESO Council gave the green light at its midyear meeting in London. Still, a 40th anniversary warrants a look at the decades passed and a reflection on the role and achievements of the organization during a period of time in which our science has progressed tremendously. That ESO has achieved its goals is undisputed, providing evidence of the wisdom of those astronomers who gathered in Leiden in early 1954 to formulate the need for this organization and justifying the trust displayed by the five countries, which were the original signatories to the 1962 convention that formed the legal base for ESO. Title: Forty years ESO - public anniversary activities Authors: Madsen, C. Bibcode: 2002Msngr.109...56M Altcode: Readers of The Messenger will be well aware of ESO's 40th anniversary in October this year. This is most certainly a reason for ESO's friends to celebrate. Beyond the professional astronomers, engineers and other people with direct links to the organization, this includes many people all over Europe, e.g. amateur astronomers, science teachers, and people with a general interest in science. At the same time, the European Intergovernmental Research Organizations constitute fine examples of how, through collaboration, European countries can interact and achieve ambitious goals. Thus the success of ESO reaches beyond the confines of professional Astronomy. Title: ESO in the European Parliament Authors: Madsen, C. Bibcode: 2002Msngr.108...43M Altcode: Astronomy and Astrophysics is not normally at the centre of attention at the highest political circles in Europe. However, the renaissance that our science is currently experiencing, not least based on the spectacular success of the VLT, has not gone unnoticed among the decision makers in Europe. Title: ESO Presentation in Brussels Authors: Madsen, C. Bibcode: 2001Msngr.106...48M Altcode: No abstract at ADS Title: Latest News: ESO High-Level Presentation in Porto Authors: Madsen, C. Bibcode: 2001Msngr.104...21M Altcode: No abstract at ADS Title: Success for ``Physics on Stage'' Festival in Geneva Authors: Madsen, C.; West, R. Bibcode: 2000Msngr.102...29M Altcode: Can you imagine how much physics is in a simple match of ping-pong, in throwing a boomerang, or in a musical concert? Physics is all around us and governs our lives. But who is going to maintain these technologies and develop new ones in the future? Recent surveys show a frightening decline of interest in physics and technology among E u r o p e 's citizens, especially school children. Fewer and fewer young people enrol in physics courses at Europe's universities while scepticism towards science and technology is spreading and causing great concern among governments and educators. Title: Public outreach in astronomy: The ESO experience Authors: Madsen, C.; West, R. M. Bibcode: 2000ASSL..250...25M Altcode: 2000iha..conf...25M No abstract at ADS Title: Science with the Atacama Millimetre Array Authors: Madsen, C. Bibcode: 1999Msngr..98...56M Altcode: Science with the Atacama Large Millimetre Array Title: ESO at the Hannover Fair Authors: Madsen, C. Bibcode: 1999Msngr..96...29M Altcode: The Hannover Fair is the world's largest industrial fair. Each year more than 300,000 visitors from all over the world attend this major event which occupies 30 large exhibition halls. This year, about 7300 enterprises from 63 countries demonstrated their latest products and services, either at individual stands or within ‘national' information stands. Title: Award for the ESO VLT Project Authors: Madsen, C. Bibcode: 1998Msngr..94...38M Altcode: Naturally, ‘First Light' for the first of the VLT Unit Telescopes has not gone unnoticed by the astronomical community. However, also newspapers, magazines, radio and TV have reported widely about this new facility and about the first, fascinating pictures that were obtained with UT1. Another sign of the world-wide attention that the VLT has caught was the fact that the well-known US magazine Popular Science chose the project for one of the coveted “The Best of What's New Awards” for 1998, given to the 100 most important technology developments in the course of the year. The construction of the VLT was recognised as an “outstanding achievement” within the “Aviation and Space” category. Title: Sea & Space - A Successful Educational Project for Europe's Secondary Schools Authors: Madsen, C.; West, R. Bibcode: 1998Msngr..93...44M Altcode: There are many links between the Sea and the Space surrounding us. Indeed, Space itself is often likened with a new and uncharted Ocean on which we now continue the great voyages of discovery of the past. Space-based satellites allow us to study the processes in the Earth's oceans in unprecedented detail and at the same time to verify complex principles in fundamental sciences like physics, chemistry and mathematics. Space is also our tenuous link to the distant places from where the ingredients of life first came to our planet, and the ocean is where they began the incredible evolutionary processes of which we ourselves are a product. Title: Astronomy On-Line - the World's Biggest Astronomy Event on the World-Wide-Web Authors: Albrecht, R.; West, R.; Naumann, M.; Madsen, C. Bibcode: 1998ASPC..145..248A Altcode: 1998adass...7..248A This educational programme was organised in a collaboration between ESO, the European Association for Astronomy Education (EAAE) and the European Union (EU) during the 4th European Week for Scientific and Technological Culture. Astronomy On-Line brought together about 5000 students from all over Europe and other continents. Learning to use the vast resources of tomorrow's communication technology, they also experienced the excitement of real-time scientific adventure and the virtues of international collaboration. Title: ESO at the Leipzig fair Authors: Madsen, C. Bibcode: 1997Msngr..89...13M Altcode: No abstract at ADS Title: The astronomy on-line project. Authors: West, R.; Madsen, C. Bibcode: 1997Msngr..87...51W Altcode: A major Web-based educational programme, known as Astronomy On-Line, has just taken place in close collaboration between the European Association for Astronomy Education (EAAE), the European Southern Observatory and the European Union. Title: The King of Sweden Visits ESO Exhibition Authors: Madsen, C. Bibcode: 1996Msngr..84...36M Altcode: No abstract at ADS Title: ESO Exhibition in Florence Authors: Madsen, C. Bibcode: 1993Msngr..72...10M Altcode: No abstract at ADS Title: ESO at CNRS Plenary Meeting Authors: Madsen, C. Bibcode: 1993Msngr..72...12M Altcode: No abstract at ADS Title: "Exploring the Universe" from the Desert Gate Authors: Madsen, C. Bibcode: 1992Msngr..70...24M Altcode: No abstract at ADS Title: ESO exhibitions in Chile - a tremendous success. Authors: Bouchet, P.; Cabillic, A.; Madsen, C. Bibcode: 1992Msngr..68...18B Altcode: No abstract at ADS Title: ESO at Expo '92 Authors: Madsen, C. Bibcode: 1992Msngr..67...48M Altcode: No abstract at ADS Title: Impressions from the XXI IAU General Assembly. Authors: Baade, D.; Merkle, F.; Traat, P.; Sterken, C.; Grosbøl, P.; Rosa, M.; Madsen, C.; Warmels, R.; van der Laan, H. Bibcode: 1991Msngr..65...17B Altcode: No abstract at ADS Title: Planeta Terra - Nosso Destino Comum Authors: Madsen, C. Bibcode: 1991Msngr..64...60M Altcode: No abstract at ADS Title: NGC 5084: a massive disc galaxy with a tilted ring. Authors: Zeilinger, W. W.; Galletta, G.; Madsen, C. Bibcode: 1990MNRAS.246..324Z Altcode: Spectroscopic and photometric observations of the edge-on galaxy NGC 5084 are presented and discussed. The galaxy exhibits a very faint outer structure which is is almost straight in projection, but is tilted by ~5^deg^ with respect to the brighter, inner stellar disc. Stellar and gas rotation curves at different position angles are presented, as well as accurate CCD surface photometry in Gunn i waveband. A geometrical analysis of the galaxy component is conducted on PDS tracings from ESO and ESO/SRC Sky Atlas copies. It is suggested that the tilt between the above components is due to the warping of the main galaxy plane, with the gas confined to a ring occupying its outer edge. If this is so, the apparent misalignment is only due to the lack of matter at intermediate radii. A three-component galaxy model has been used to correct the stellar rotation curve for the effects of integration along the line-of-sight and asymmetric drift. The resulting curve is in good agreement with the H I results in the outer parts. From this model, a 3D mass and light distribution has been derived and hence the mass-to-light ratio at various radii. This ratio varies from ~19 M_sun_/L_sun_ in the inner disc, up to ~45 M_sun_/L_sun_ in the outskirts, and there is a possible central peak with M/L > 30 M_sun_/L_sun_. A massive, dark halo is required to explain the galaxy dynamics, which place NGC 5084 among the supermassive disc galaxies. The presence of this dark halo offers a mechanism that could stabilize the warped disc. The possible external origin of the warped disc is discussed. Title: BBC Makes ESO Film Authors: Madsen, C. Bibcode: 1990Msngr..59...20M Altcode: BBC Makes ESO Film Title: ESO at World Tech Vienna Authors: Madsen, C. Bibcode: 1989Msngr..57...33M Altcode: No abstract at ADS Title: Signposts of low mass star formation in molecular clouds. Authors: Reipurth, B.; Madsen, C. Bibcode: 1989Msngr..55...32R Altcode: Regions of massive star formation are easily recognizable because of the presence of bright, often very extended H11 regions. The more quiescent places where only low mass star formation takes place are not so immediately obvious to identify. Most of the low mass star forming regions known today were found in the 1950's, mainly through objective prism surveys for Ha emission stars done by Joy, Herbig, Haro and others. Their results are summarized and supplemented by later findings in a new catalogue by Herbig and Bell (1988), which Iists 742 mainly low mass pre-main-sequence stars. Another recent and rich source of low mass young stars is the IRAS catalogue. IRAS data towards clouds, however, often suffer from source confusion and, in particular, extraction problems because of background emission. Title: The Changing of Skyline of La Silla Authors: Madsen, C. Bibcode: 1989Msngr..55...31M Altcode: 1989Msngr..55...31. The Changing of Skyline of La Silla Title: Book-Review - Exploring the Southern Sky Authors: Laustsen, S.; Madsen, C.; West, R. M.; Kutyrev, A. S. Bibcode: 1988SvA....32..695L Altcode: No abstract at ADS Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas from the European Southern Observatory Authors: Laustsen, S.; Madsen, C.; West, R. M.; Glass, I. S. Bibcode: 1988MNSSA..47...58L Altcode: No abstract at ADS Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas from the European Southern Observatory Authors: Laustsen, S.; Madsen, C.; West, R. M.; Bhatt, H. C. Bibcode: 1988BASI...16..136L Altcode: No abstract at ADS Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas from the European Southern Observatory Authors: Laustsen, S.; Madsen, C.; West, R. M. Bibcode: 1988Sci...239Q1437L Altcode: No abstract at ADS Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas from the European Southern Observatory / ESO Authors: Laustsen, S.; Madsen, C.; West, R. M.; Mitton, J. Bibcode: 1988JBAA...98..114L Altcode: No abstract at ADS Title: Book-Review - Atlas of the Southern Hemisphere Authors: Laustsen, S.; Madsen, C.; West, R. M.; Oleak, H. Bibcode: 1988AN....309..345L Altcode: No abstract at ADS Title: A Deep High Resolution Wide Field Survey of the Milky Way (With 1 Figures) Authors: Madsen, C. Bibcode: 1988astr.conf..210M Altcode: Generally speaking, objects in the Milky Way are probably the most observed astronomical objects. To obtain an overview of the Milky Way band, wide angle photography becomes necessary. Consequently a number of observers have produced wide angle photographs or full panoramas by making mosaics from several photographs. Most of the published photographs of the Milky Way band or parts thereof have been obtained in narrow pass-bands, such as Hα. Title: Book-Review - Exploring the Southern Sky - a Pictorial Atlas from the European-Southern Authors: Laustsen, S.; Madsen, C.; West, R. M.; Morrison, P. Bibcode: 1988SciAm.258a.104L Altcode: 1988SciAm.258..104L No abstract at ADS Title: Deep LMC Images Authors: West, R. M.; Pedersen, H.; Madsen, C. Bibcode: 1987Msngr..50...24W Altcode: One of the most observed objects in the southern sky is the Large Magellanic Cloud. It is easily seen as a naked-eye object near the southern celestial pole together with its less conspicuous neighbour, the Small Magellanic Cloud. Looking at the LMG, the casual observer discerns the elongated bar and the bright 30 Doradus nebula and, since February this year, the famous Supernova 1987 A. Title: Book-Review - Exploring the Southern Sky Authors: Laustsen, S.; Madsen, C.; West, R. M.; Hughes, D. W. Bibcode: 1987Natur.330..618L Altcode: No abstract at ADS Title: Supernova 1987A in the Large Magellanic Cloud Authors: West, R. M.; Madsen, C.; Bahcall, J.; Dar, A.; Piran, T.; Murdin, P.; Beresford, T. Bibcode: 1987IAUC.4329....2W Altcode: 1987IAUC.4329....1W; 1987IAUC.4329....0W R. M. West, European Southern Observatory, informs us that a color exposure (Agfachrome 1000 RS, Hasselblad 6 x 6) of the LMC was made by C. Madsen at La Silla during Feb. 23.042-23.056 UT. Sanduleak -69 202 is just seen near the limiting magnitude of about 12. J. Bahcall, A. Dar and T. Piran, Institute for Advanced Study, Princeton, communicate the following note, prepared in advance of the report of the neutrino detection on IAUC 4323: "We have calculated the event rate expected in terrestrial neutrino detectors from neutrinos produced in the formation of the neutron star in the LMC supernova. Using neutrino fluxes from a model stellar collapse calculation of Wilson et al. and cross sections from Bahcall, we estimate that only about one atom of Ar is produced in the Davis Cl tank, but that about 50 electron recoils, with energies of about 10 MeV, are produced in the Kamiokande II water detector. We also estimate about 3 events each in the scintillators of the University of Pennsylvania (Homestake Mine) and the Italian- Russian collaboration (Mont Blanc). The results are sensitive to the effective temperature of the emitted neutrino spectrum." P. Murdin, Royal Greenwich Observatory, reports: "It is not clear whether the relative constancy of the light curve of SN 1987A from Feb. 25 to Mar. 3 represents the maximum in a typical type II light curve or the 20 day premaximum halt seen in SN 1940B and 1941A. If SN 1987A follows precedent, either it will decline soon to mag 6, where it will remain in the post-maximum plateau until early May, or it will brighten in mid-March to a maximum at mag about 2, remaining brighter than mag 6 until early July. Observers should be aware of this uncertainty when planning observations." Visual magnitude estimate by T. Beresford, Adelaide, South Australia: Mar. 3.42 UT, 4.3. Title: Wide angle photography of the Milky Way. Authors: Madsen, C.; Laustsen, S. Bibcode: 1986Msngr..46...12M Altcode: Since astronomers began to use photography on a scientific basis, a number of pictures of the Milky Way band, or large parts thereof, has been made. Barnard (1890, 1927) produced a series of fine Milky Way photos. Later attempts by Rodgers, Whiteoak et al. (1960), Schmidt-Kaler and Schlosser (1972), Sivan (1974) and others resulted in impressive pictures, either in the form of panoramas or extreme wide-field views, mostly in weil defined (narrow) spectral bands. The most famous depietion of the Milky Way, however, is not a photograph but a drawing made by hand. This was made by M. and T. Keskula at Lund Observatory, and it has become the standard representation of the Milky Way band in textbooks. Title: Some nonatlas work at the European Southern Observatory (ESO) Sky Atlas Laboratory Authors: Madsen, C. Bibcode: 1984asph.conf..143M Altcode: 1984asph.rept..143M Black and white and color astronomical photography at the European Southern Observatory is described. For black and white copying, unsharp masking, diffuse light amplification (DLA), and integrated printing are used. To reduce noise in DLA plate surfaces, several enhanced derivatives are printed together. Color photographs are produced by contact printing. The application of false color composites for fast location of excess UV objects is described. Title: Some non-atlas work at ESO Sky Atlas Laboratory. Authors: Madsen, C. Bibcode: 1984ORROE..14..143M Altcode: The ESO Sky Atlas Laboratory (SAL) was set up in 1972 with the aim of producing the ESO Quick Blue Survey and later the joint ESO/SERC Survey of the Southern Sky. With the establishment of a Scientific Group, it became apparent that ESO had additional photographic needs, the fullfilment of which was also entrusted to SAL. Thus, in the course of the years, the "Photographic Section" evolved as a subdivision of the Sky Atlas Laboratory. Title: Technical photography at ESO Sky Atlas Laboratory. Authors: West, R. M.; Diebold, L.; Dumoulin, B.; Madsen, C.; Québatte, J.; Völk, E.; Zodet, H. Bibcode: 1984ESOTR..14.....W Altcode: No abstract at ADS Title: Moderne photographische Kopiermethoden in der Astronomie Authors: Madsen, C. Bibcode: 1984MitAG..62..175M Altcode: No abstract at ADS Title: Tirage en couleur de photographies astronomiques à l'Observatoire Européen Austral. Authors: Madsen, C.; Tarenghi, M. Bibcode: 1983LAstr..97..376M Altcode: No abstract at ADS Title: A Dust lane in NGC 6251. Authors: Nieto, J. -L.; Coupinot, G.; Lelievre, G.; Madsen, C. Bibcode: 1983MNRAS.203P..39N Altcode: A dust lane cutting the central region of the radio galaxy NGC 6251 along its minor axis has been observed. This dust lane is roughly parallel to the radio jet. The implications of this observation are discussed: (1) NGC 6251 resembles a prolate object, morphologically at least. (2) Since the jet is remarkably linear, the configuration of the dust lane-stellar potential-nucleus system is probably quite stable. The dust lane may be responsible for the bending of the jet outwards. (3) Time-scale arguments relative to a possible merging suggest a rather slow non-relativistic motion. (4) The orientation of the dust lane does not support the suggestion by Kotanyi & Ekers of a correlation between the axis of rotation of the gaseous disc and the jet axis in a radio galaxy, or of a correlation between the alignment of both rotation and jet axes with the power of the source. Title: Fotografisk arbejde hos ESO. Authors: Madsen, C. Bibcode: 1983ATi....16..109M Altcode: No abstract at ADS Title: Astronomical Color Printing at ESO Authors: Madsen, C.; Tarenghi, M. Bibcode: 1982Msngr..30...15M Altcode: When the photographic labs in the new Garching Headquarters were planned, the installation of a colour lab was also foreseen. Following the removal from Geneva, a market survey of available colour equipment was carried out, leading to the purchase of a Durst 1800 Laborator enlarger featuring a CLS 2000 colour head and a negative carrier able to accommodate 25 x 25 cm originals, an Autopan 40-60 C processing machine and various equipment for process control. Title: On the reality of minor planet (330) Adalberta Authors: West, R. M.; Madsen, C.; Schmadel, L. D. Bibcode: 1982A&A...110..198W Altcode: It is argued that the minor planet (330) Adalberta, as discovered photographically by Wolf in 1892, is nonexistent. It appears that the two positions of the planet refer to galactic stars which, mainly due to differences in the limiting magnitudes of the plates, simulated a moving object. It is proposed that (330) Adalberta be deleted from the minor planet list. Title: Photographic Image Manipulation Authors: Madsen, C. Bibcode: 1982Msngr..28...19M Altcode: The Messenger No. 25 contained a short, general description of the non-atlas work being done in the Sky Atlas Laboratory. Briefly mentioned in the article were contrast manipulating methods ranging from masking-to reduce the contrast of a picture--to contrast enhancing methods used to obtain printable negatives (or positives). Here the procedure, the advantages and the problems connected with masking and image amplification, will be described in some detail. Title: (330) Adalberta Authors: West, R. M.; Madsen, C.; Schmadel, L. D.; Wolf, M. Bibcode: 1982IAUC.3672....2W Altcode: R. M. West and C. Madsen, European Southern Observatory; and L. D. Schmadel, Astronomisches Rechen-Institut, inform us that this notorious minor planet, allegedly observed by M. Wolf on two nights only in 1892 March, does not exist. A careful reexamination of the original Heidelberg plates shows that Wolf's two measurements refer to galactic stars. Title: Non-Atlas Photographic Work in the ESO Sky Atlas Laboratory Authors: Madsen, C. Bibcode: 1981Msngr..25...16M Altcode: As is weil known to the readers of the MESSENGER, the ESO Sky Atlas Laboratory was established to set up and undertake the production of the ESO/SRC Sky surveys. To fulfil its duties, a number of dark rooms were set up and, after some years of hard work, techniques were developed which permit limited mass-production without sacrificing the quality which has become the hallmark of this project.