Author name code: narukage ADS astronomy entries on 2022-09-14 author:"Narukage, Noriyuki" ------------------------------------------------------------------------ Title: Quiet Sun Center to Limb Variation of the Linear Polarization Observed by CLASP2 Across the Mg II h and k Lines Authors: Rachmeler, L. A.; Bueno, J. Trujillo; McKenzie, D. E.; Ishikawa, R.; Auchère, F.; Kobayashi, K.; Kano, R.; Okamoto, T. J.; Bethge, C. W.; Song, D.; Ballester, E. Alsina; Belluzzi, L.; Pino Alemán, T. del; Ramos, A. Asensio; Yoshida, M.; Shimizu, T.; Winebarger, A.; Kobelski, A. R.; Vigil, G. D.; Pontieu, B. De; Narukage, N.; Kubo, M.; Sakao, T.; Hara, H.; Suematsu, Y.; Štěpán, J.; Carlsson, M.; Leenaarts, J. Bibcode: 2022ApJ...936...67R Altcode: 2022arXiv220701788R The CLASP2 (Chromospheric LAyer Spectro-Polarimeter 2) sounding rocket mission was launched on 2019 April 11. CLASP2 measured the four Stokes parameters of the Mg II h and k spectral region around 2800 Å along a 200″ slit at three locations on the solar disk, achieving the first spatially and spectrally resolved observations of the solar polarization in this near-ultraviolet region. The focus of the work presented here is the center-to-limb variation of the linear polarization across these resonance lines, which is produced by the scattering of anisotropic radiation in the solar atmosphere. The linear polarization signals of the Mg II h and k lines are sensitive to the magnetic field from the low to the upper chromosphere through the Hanle and magneto-optical effects. We compare the observations to theoretical predictions from radiative transfer calculations in unmagnetized semiempirical models, arguing that magnetic fields and horizontal inhomogeneities are needed to explain the observed polarization signals and spatial variations. This comparison is an important step in both validating and refining our understanding of the physical origin of these polarization signatures, and also in paving the way toward future space telescopes for probing the magnetic fields of the solar upper atmosphere via ultraviolet spectropolarimetry. Title: Study of Time Evolution of Thermal and Nonthermal Emission from an M-class Solar Flare Authors: Nagasawa, Shunsaku; Kawate, Tomoko; Narukage, Noriyuki; Takahashi, Tadayuki; Caspi, Amir; Woods, Thomas N. Bibcode: 2022ApJ...933..173N Altcode: 2022arXiv220514369N We conduct a wide-band X-ray spectral analysis in the energy range of 1.5-100 keV to study the time evolution of the M7.6-class flare of 2016 July 23, with the Miniature X-ray Solar Spectrometer (MinXSS) CubeSat and the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) spacecraft. With the combination of MinXSS for soft X-rays and RHESSI for hard X-rays, a nonthermal component and three-temperature multithermal component-"cool" (T ≍ 3 MK), "hot" (T ≍ 15 MK), and "superhot" (T ≍ 30 MK)-were measured simultaneously. In addition, we successfully obtained the spectral evolution of the multithermal and nonthermal components with a 10 s cadence, which corresponds to the Alfvén timescale in the solar corona. We find that the emission measures of the cool and hot thermal components are drastically increasing more than hundreds of times and the superhot thermal component is gradually appearing after the peak of the nonthermal emission. We also study the microwave spectra obtained by the Nobeyama Radio Polarimeters, and we find that there is continuous gyrosynchrotron emission from mildly relativistic nonthermal electrons. In addition, we conducted a differential emission measure (DEM) analysis by using Atmospheric Imaging Assembly on board the Solar Dynamics Observatory and determined that the DEM of cool plasma increases within the flaring loop. We find that the cool and hot plasma components are associated with chromospheric evaporation. The superhot plasma component could be explained by the thermalization of the nonthermal electrons trapped in the flaring loop. Title: On the faintest solar coronal hard X-rays observed with FOXSI Authors: Buitrago-Casas, Juan Camilo; Glesener, Lindsay; Christe, Steven; Krucker, Säm; Vievering, Juliana; Athiray, P. S.; Musset, Sophie; Davis, Lance; Courtade, Sasha; Dalton, Gregory; Turin, Paul; Turin, Zoe; Ramsey, Brian; Bongiorno, Stephen; Ryan, Daniel; Takahashi, Tadayuki; Furukawa, Kento; Watanabe, Shin; Narukage, Noriyuki; Ishikawa, Shin-nosuke; Mitsuishi, Ikuyuki; Hagino, Kouichi; Shourt, Van; Duncan, Jessie; Zhang, Yixian; Bale, Stuart D. Bibcode: 2022arXiv220504291B Altcode: Solar nanoflares are small eruptive events releasing magnetic energy in the quiet corona. If nanoflares follow the same physics as their larger counterparts, they should emit hard X-rays (HXRs) but with a rather faint intensity. A copious and continuous presence of nanoflares would deliver enormous amounts of energy into the solar corona, possibly accounting for its high temperatures. To date, there has not been any direct observation of such sustained and persistent HXRs from the quiescent Sun. However, Hannah et al. in 2010 constrained the quiet Sun HXR emission using almost 12 days of quiescent solar-off-pointing observations by RHESSI. These observations set upper limits at $3.4\times 10^{-2}$ photons$^{-1}$ s$^{-1}$ cm$^{-2}$ keV$^{-1}$ and $9.5\times 10^{-4}$ photons$^{-1}$ s$^{-1}$ cm$^{-2}$ keV$^{-1}$ for the 3-6 keV and 6-12 keV energy ranges, respectively. Observing feeble HXRs is challenging because it demands high sensitivity and dynamic range instruments in HXRs. The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment excels in these two attributes. Particularly, FOXSI completed its third successful flight (FOXSI-3) on September 7th, 2018. During FOXSI-3's flight, the Sun exhibited a fairly quiet configuration, displaying only one aged non-flaring active region. Using the entire $\sim$6.5 minutes of FOXSI-3 data, we constrained the quiet Sun emission in HXRs. We found $2\sigma$ upper limits in the order of $\sim 10^{-3}$ photons$^{-1}$ s$^{-1}$ cm$^{-2}$ keV$^{-1}$ for the 5-10 keV energy range. FOXSI-3's upper limit is consistent with what was reported by Hannah et al., 2010, but FOXSI-3 achieved this result using $\sim$1/2640 less time than RHESSI. A possible future spacecraft using FOXSI's concept would allow enough observation time to constrain the current HXR quiet Sun limits further or perhaps even make direct detections. Title: Empirical relations between the intensities of Lyman lines of H and He+ Authors: Gordino, M.; Auchère, F.; Vial, J. -C.; Bocchialini, K.; Hassler, D. M.; Bando, T.; Ishikawa, R.; Kano, R.; Kobayashi, K.; Narukage, N.; Trujillo Bueno, J.; Winebarger, A. Bibcode: 2022A&A...657A..86G Altcode: 2022arXiv220101519G Context. Empirical relations between major UV and extreme UV spectral lines are one of the inputs for models of chromospheric and coronal spectral radiances and irradiances. They are also needed for the interpretation of some of the observations of the Solar Orbiter mission.
Aims: We aim to determine an empirical relation between the intensities of the H I 121.6 nm and He II 30.4 nm Ly-α lines.
Methods: Images at 121.6 nm from the Chromospheric Lyman-Alpha Spectro Polarimeter (CLASP) and Multiple XUV Imager (MXUVI) sounding rockets were co-registered with simultaneous images at 30.4 nm from the EIT and AIA orbital telescopes in order to derive a spatially resolved relationship between the intensities.
Results: We have obtained a relationship between the H I 121.6 nm and He II 30.4 nm intensities that is valid for a wide range of solar features, intensities, and activity levels. Additional SUMER data have allowed the derivation of another relation between the H I 102.5 nm (Ly-β) and He II 30.4 nm lines for quiet-Sun regions. We combined these two relationships to obtain a Ly-α/Ly-β intensity ratio that is comparable to the few previously published results.
Conclusions: The relationship between the H I 121.6 nm and He II 30.4 nm lines is consistent with the one previously obtained using irradiance data. We have also observed that this relation is stable in time but that its accuracy depends on the spatial resolution of the observations. The derived Ly-α/Ly-β intensity ratio is also compatible with previous results. Title: Hard X-ray upper limits of the quiet Sun with new FOXSI observations Authors: Buitrago-Casas, Juan Camilo; Glesener, Lindsay; Christe, Steven; Krucker, Sam; Vievering, Juliana; Athiray, P. S.; Musset, Sophie; Davis, Lance; Courtade, Sasha; Dalton, Gregory; Turin, Paul; Turin, Zoe; Ramsey, Brian; Bongiorno, Stephen; Ryan, Daniel; Takahashi, Tadayuki; Furukawa, Kento; Watanabe, Shin; Narukage, Noriyuki; Ishikawa, Shin-nosuke; Mitsuishi, Ikuyuki; Hagino, Kouichi Bibcode: 2021AGUFMSH51A..04B Altcode: Solar nanoflares are small eruptive events releasing magnetic energy in the quiet corona. If nanoflares follow the same physics as their larger counterparts, they should emit hard X-rays (HXRs) but with a rather faint intensity. A copious and continuous presence of nanoflares would result in a sustained and persistent emission in HXRs, which in turn would deliver enormous amounts of energy into the solar corona, possibly accounting for its high temperatures. To date, there has not been any direct observation of such sustained and persistent HXRs from the quiescent Sun. However, Hannah et al. in 2010 constrained the quiet Sun HXR emission using almost 12 days of quiescent solar-off-pointing observations by RHESSI. These observations set $2\sigma$ upper limits at $3.4\times 10^{-2}$ photons$^{-1}$ s$^{-1}$ cm$^{-2}$ keV$^{-1}$ and $9.5\times 10^{-4}$ photons$^{-1}$ s$^{-1}$ cm$^{-2}$ keV$^{-1}$ for the 3-6 keV and 6-12 keV energy ranges, respectively. Observing feeble HXRs is challenging because it demands high sensitivity and dynamic range instruments in the HXR energy band. The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment excels in these two attributes when compared with RHESSI. Particularly, FOXSI completed its third successful flight (FOXSI-3) on September 7th, 2018. During FOXSI-3s flight, the Sun exhibited a fairly quiet configuration, displaying only one aged non-flaring active region. Using the entire $\sim$6.5 minutes of FOXSI-3 data, we constrained the quiet Sun emission in HXRs. We found $2\sigma$ upper limits in the order of $\sim 10^{-3}$ photons$^{-1}$ s$^{-1}$ cm$^{-2}$ keV$^{-1}$ for the 5-10 keV energy range. FOXSI-3's upper limit is consistent with what was reported by Hannah et al., 2010, but FOXSI-3 achieved this result using $\sim$1/2640 less time than RHESSI. A possible future spacecraft using FOXSI's concept would allow enough observation time to constrain the current HXR quiet Sun limits further or perhaps even make direct detections. Title: The FOXSI-4 Sounding Rocket: High Resolution Focused X-ray Observations of the Sun Authors: Glesener, Lindsay; Buitrago-Casas, Juan Camilo; Vievering, Juliana; Pantazides, Athanasios; Musset, Sophie; Panchapakesan, Subramania Athiray; Baumgartner, Wayne; Bongiorno, Stephen; Champey, Patrick; Christe, Steven; Courtade, Sasha; Duncan, Jessie; Ishikawa, Shin-nosuke; Krucker, Sam; Martinez Oliveros, Juan Carlos; Perez-Piel, Savannah; Mitsuishi, Ikuyuki; Narukage, Noriyuki; Ryan, Daniel; Takahashi, Tadayuki; Watanabe, Shin Bibcode: 2021AGUFMSH55B1831G Altcode: It has been firmly demonstrated that direct-focusing instruments can transform the way high-energy X-rays from astronomical objects, including the Sun, are measured. The NuSTAR spacecraft has increased the sensitivity to faint astrophysical sources by 100 times as compared with previous, indirect, imagers. The first three flights of the Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket established the usefulness and feasibility of a similar method optimized for the Sun, and showed that in addition to greater sensitivity, a vastly improved dynamic range can be obtained in this way. This technology stands ready to revolutionize understanding of solar flares by elucidating particle acceleration sites in the corona, studying how electrons propagate and deposit their energies, and how accelerated particles escape into interplanetary space. While the fundamental building blocks of solar hard X-ray (HXR) focusing are in place and ready for a spacecraft mission, concurrent development is required to prepare for the next generation of high-energy solar explorers, which will require higher rate capability and higher angular resolution to investigate finer-scale structure and to better complement instruments at other wavelengths. FOXSI-4 features technological advances that enable high angular resolution as well as measurement of bright sources. In the first category, we will develop high-precision mirror production methods and finely pixelated Si CMOS sensors, and will demonstrate substrip/subpixel resolution in fine-pitch CdTe sensors. Secondly, we will demonstrate rate capability of these sensors sufficient for flare measurement, and will develop novel pixelated attenuators that optimize energy coverage even at high rates. The experiment will demonstrate these technologies in NASAs first-ever solar flare campaign, flying in tandem with the Hi-C FLARE rocket and in a campaign with the SNIFS rocket. The campaign will position multiple rocket experiments awaiting an opportunistic signal and will launch the experiments for near-simultaneous observation of the flare.This campaign will allow for direct collaboration with the Parker Solar Probe (PSP) during one of its perihelia. Title: FOXSI-4: the high resolution focusing X-ray rocket payload to observe a solar flare Authors: Buitrago-Casas, Juan Camilo; Vievering, Juliana; Musset, Sophie; Glesener, Lindsay; Athiray, P. S.; Baumgartner, Wayne; Bongiorno, Stephen; Champey, Patrick; Christe, Steven; Courtade, Sasha; Dalton, Gregory; Duncan, Jessie; Gilchrist, Kelsey; Ishikawa, Shin-nosuke; Jhabvala, Christine; Kanniainen, Hunter; Krucker, Säm.; Gregory, Kyle; Martinez Oliveros, Juan Carlos; McCracken, Jeff; Mitsuishi, Ikuyuki; Narukage, Noriyuki; Pantazides, Athanasios; Peretz, Eliad; Perez-Piel, Savannah; Ramanayaka, Aruna; Ramsey, Brian; Ryan, Danny; Savage, Sabrina; Takahashi, Tadayuki; Watanabe, Shin; Winebarger, Amy; Zhang, Yixian Bibcode: 2021SPIE11821E..0LB Altcode: The FOXSI-4 sounding rocket will fly a significantly upgraded instrument in NASA's first solar are campaign. It will deploy direct X-ray focusing optics which have revolutionized our understanding of astrophysical phenomena. For example, they have allowed NuSTAR to provide X-ray imaging and IXPE (scheduled for launch in 2021) to provide X-ray polarization observations with detectors with higher photon rate capability and greater sensitivity than their predecessors. The FOXSI sounding rocket is the first solar dedicated mission using this method and has demonstrated high sensitivity and improved imaging dynamic range with its three successful flights. Although the building blocks are already in place for a FOXSI satellite instrument, further advances are needed to equip the next generation of solar X-ray explorers. FOXSI-4 will develop and implement higher angular resolution optics/detector pairs to investigate fine spatial structures (both bright and faint) in a solar are. FOXSI-4 will use highly polished electroformed Wolter-I mirrors fabricated at the NASA/Marshall Space Flight Center (MSFC), together with finely pixelated Si CMOS sensors and fine-pitch CdTe strip detectors provided by a collaboration with institutes in Japan. FOXSI-4 will also implement a set of novel perforated attenuators that will enable both the low and high energy spectral components to be observed simultaneously in each pixel, even at the high rates expected from a medium (or large) size solar are. The campaign will take place during one of the Parker Solar Probe (PSP) perihelia, allowing coordination between this spacecraft and other instruments which observe the Sun at different wavelengths. Title: Assessing quiet Sun hard X-rays using observations from the FOXSI Sounding Rockets Authors: Buitrago-Casas, J.; Glesener, L.; Christe, S.; Krucker, S.; Vievering, J.; Athiray, P.; Musset, S.; Ryan, D.; Ishikawa, S.; Narukage, N.; Bongiorno, S.; Furukawa, K.; Ramsey, B.; Courtade, S.; Dalton, G.; Turin, P.; Takahashi, T.; Watanabe, S.; Mitsuishi, I.; Hagino, K.; Duncan, J. Bibcode: 2021AAS...23810604B Altcode: In solar and helio-physics, the coronal heating problem relates to the question of identifying and explaining the mechanism(s) causing the corona's temperatures to be a few hundred times hotter than the solar surface. Among the various plausible hypotheses proposed to explain this problem, one of the strongest candidates relates to copious low energy magnetic reconnections (nanoflares) occurring throughout the solar corona. When examined thoroughly, this mechanism implies heating that happens impulsively on individual flux tubes (strands). Emission of hard X-rays (HXRs) should be a consequence of such non-thermal phenomena, or even of purely thermal transients, if hot enough. In quiescent solar corona areas, nanoflares should manifest in HXRs via very faint signatures covering vast regions. Observing feeble HXRs demands an instrument with high sensitivity and dynamic range for energies between 4 and 15 keV. FOXSI (which stands for the Focusing Optics X-ray Solar Imager) is such an instrument. As a payload of a NASA/LCAS (low-cost access to space program) sounding rocket, FOXSI has successfully completed three launches. The two most recent flights (FOXSI-2 and -3) included quiescent areas of the Sun as part of the targets. For this presentation, we will show a full assessment of the HXR flux from the quiet Sun observed with FOXSI. We begin by presenting a thorough characterization of the stray light (ghost rays) impinging into FOXSI's detectors caused by sources outside of the field of view. We then identify areas free of ghost rays where the instrument sensitivity reaches a maximum to quiet Sun HXR detections. Finally, we implement a Bayesian (known as ON/OFF analysis) to estimate an upper detectability threshold of quiet Sun HXRs and a probability distribution for quiet-Sun HXR fluxes when sources are supposed to exist. Title: Mapping of Solar Magnetic Fields from the Photosphere to the Top of the Chromosphere with CLASP2 Authors: McKenzie, D.; Ishikawa, R.; Trujillo Bueno, J.; Auchere, F.; del Pino Aleman, T.; Okamoto, T.; Kano, R.; Song, D.; Yoshida, M.; Rachmeler, L.; Kobayashi, K.; Narukage, N.; Kubo, M.; Ishikawa, S.; Hara, H.; Suematsu, Y.; Sakao, T.; Bethge, C.; De Pontieu, B.; Vigil, G.; Winebarger, A.; Alsina Ballester, E.; Belluzzi, L.; Stepan, J.; Asensio Ramos, A.; Carlsson, M.; Leenaarts, J. Bibcode: 2021AAS...23810603M Altcode: Coronal heating, chromospheric heating, and the heating & acceleration of the solar wind, are well-known problems in solar physics. Additionally, knowledge of the magnetic energy that powers solar flares and coronal mass ejections, important drivers of space weather, is handicapped by imperfect determination of the magnetic field in the sun's atmosphere. Extrapolation of photospheric magnetic measurements into the corona is fraught with difficulties and uncertainties, partly due to the vastly different plasma beta between the photosphere and the corona. Better results in understanding the coronal magnetic field should be derived from measurements of the magnetic field in the chromosphere. To that end, we are pursuing quantitative determination of the magnetic field in the chromosphere, where plasma beta transitions from greater than unity to less than unity, via ultraviolet spectropolarimetry. The CLASP2 mission, flown on a sounding rocket in April 2019, succeeded in measuring all four Stokes polarization parameters in UV spectral lines formed by singly ionized Magnesium and neutral Manganese. Because these ions produce spectral lines under different conditions, CLASP2 thus was able to quantify the magnetic field properties at multiple heights in the chromosphere simultaneously, as shown in the recent paper by Ishikawa et al. In this presentation we will report the findings of CLASP2, demonstrating the variation of magnetic fields along a track on the solar surface and as a function of height in the chromosphere; and we will illustrate what is next for the CLASP missions and the demonstration of UV spectropolarimetry in the solar chromosphere. Title: High Resolution FOXSI: The Development Of FOXSI-4 Authors: Glesener, L.; Buitrago-Casas, J.; Duncan, J.; Nagasawa, S.; Pantazides, A.; Perez-Piel, S.; Zhang, Y.; Vievering, J.; Musset, S.; Panchapakesan, S.; Baumgartner, W.; Bongiorno, S.; Champey, P.; Christe, S.; Courtade, S.; Kanniainen, H.; Krucker, S.; Ishikawa, S.; Martinez Oliveros, J.; Mitsuishi, I.; Narukage, N.; Peretz, E.; Ryan, D.; Takahashi, T.; Watanabe, S.; Winebarger, A. Bibcode: 2021AAS...23831301G Altcode: It has been firmly demonstrated that direct-focusing instruments can transform the way high-energy X-rays from astronomical objects, including the Sun, are measured. The NuSTAR spacecraft has increased the sensitivity to faint astrophysical sources by 100 times as compared with previous, indirect, imagers. The first three flights of the Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket established the usefulness and feasibility of a similar method optimized for the Sun, and showed that in addition to greater sensitivity, a vastly improved dynamic range can be obtained in this way. This technology stands ready to revolutionize understanding of solar flares by elucidating particle acceleration sites in the corona, studying how electrons propagate and deposit their energies, and how accelerated particles escape into interplanetary space. While the fundamental building blocks of solar hard X-ray (HXR) focusing are in place and ready for a spacecraft mission, concurrent development is required to prepare for a subsequent generation of high-energy solar explorers, which will require higher rate capability and higher angular resolution to investigate finer-scale structure and to better complement instruments at other wavelengths.The fourth flight of FOXSI (FOXSI-4) features technological advances that enable high angular resolution as well as measurement of bright sources. In the first category, we are developing high-precision mirror production methods and finely pixelated Si CMOS sensors, and will demonstrate substrip/subpixel resolution in fine-pitch CdTe sensors. Secondly, we will demonstrate a rate capability of these sensors sufficient for flare measurement, and are developing novel pixelated attenuators that optimize energy coverage even at high rates.The experiment will demonstrate these technologies in NASA's first-ever solar flare campaign, flying in tandem with the Hi-C FLARE rocket and on the same campaign as the SNIFS rocket. The campaign will position multiple rocket experiments awaiting an opportunistic signal and will launch multiple payloads for near-simultaneous observation of the flare.This campaign will allow for direct collaboration with the Parker Solar Probe (PSP) during one of its perihelia. Title: Mapping solar magnetic fields from the photosphere to the base of the corona Authors: Ishikawa, Ryohko; Bueno, Javier Trujillo; del Pino Alemán, Tanausú; Okamoto, Takenori J.; McKenzie, David E.; Auchère, Frédéric; Kano, Ryouhei; Song, Donguk; Yoshida, Masaki; Rachmeler, Laurel A.; Kobayashi, Ken; Hara, Hirohisa; Kubo, Masahito; Narukage, Noriyuki; Sakao, Taro; Shimizu, Toshifumi; Suematsu, Yoshinori; Bethge, Christian; De Pontieu, Bart; Dalda, Alberto Sainz; Vigil, Genevieve D.; Winebarger, Amy; Ballester, Ernest Alsina; Belluzzi, Luca; Štěpán, Jiří; Ramos, Andrés Asensio; Carlsson, Mats; Leenaarts, Jorrit Bibcode: 2021SciA....7.8406I Altcode: 2021arXiv210301583I Routine ultraviolet imaging of the Sun's upper atmosphere shows the spectacular manifestation of solar activity; yet we remain blind to its main driver, the magnetic field. Here we report unprecedented spectropolarimetric observations of an active region plage and its surrounding enhanced network, showing circular polarization in ultraviolet (Mg II $h$ & $k$ and Mn I) and visible (Fe I) lines. We infer the longitudinal magnetic field from the photosphere to the very upper chromosphere. At the top of the plage chromosphere the field strengths reach more than 300 gauss, strongly correlated with the Mg II $k$ line core intensity and the electron pressure. This unique mapping shows how the magnetic field couples the different atmospheric layers and reveals the magnetic origin of the heating in the plage chromosphere. Title: Optical design of the Chromospheric LAyer Spectro-Polarimeter (CLASP2) Authors: Tsuzuki, Toshihiro; Ishikawa, Ryohko; Kano, Ryouhei; Narukage, Noriyuki; Song, Donguk; Yoshida, Masaki; Uraguchi, Fumihiro; Okamoto, Takenori J.; McKenzie, David; Kobayashi, Ken; Rachmeler, Laurel; Auchere, Frederic; Trujillo Bueno, Javier Bibcode: 2020SPIE11444E..6WT Altcode: Chromospheric LAyer Spectro-Polarimeter (CLASP2) was a sounding rocket experiment, which is a follow-up mission to the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP1) in 2015. To measure the magnetic fields in the upper solar atmosphere in a highly quantitative manner, CLASP2 changes the target wavelengths from the hydrogen Ly-α line (121.567 nm) to Mg II lines near 280 nm. We reused the main structure and most of the optical components in the CLASP1 instrument, which reduced the turnaround time and cost. We added a magnifying optical system to maintain the wavelength resolution, even at the longer wavelength of CLASP2. Here, we describe the optical design and performance of the CLASP2 instrument. Title: The FOXSI-4 Sounding Rocket: High Resolution Focused X-ray Observations of the Sun Authors: Glesener, L.; Buitrago-Casas, J. C.; Musset, S.; Vievering, J. T.; Athiray, P. S.; Baumgartner, W.; Bongiorno, S.; Champey, P. R.; Christe, S.; Courtade, S.; Duncan, J. M.; Ishikawa, S. N.; Krucker, S.; Martinez Oliveros, J. C.; Mitsuishi, I.; Narukage, N.; Ryan, D.; Takahashi, T.; Watanabe, S.; Winebarger, A. R. Bibcode: 2020AGUFMSH0480011G Altcode: It has been firmly demonstrated that direct-focusing instruments can transform the way high-energy X-rays from astronomical objects, including the Sun, are measured. The NuSTAR spacecraft has increased the sensitivity to faint astrophysical sources by 100 times as compared with previous, indirect, imagers. The first three flights of the Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket established the usefulness and feasibility of a similar method optimized for the Sun, and showed that in addition to greater sensitivity, a vastly improved dynamic range can be obtained in this way. This technology stands ready to revolutionize understanding of solar flares by elucidating particle acceleration sites in the corona, studying how electrons propagate and deposit their energies, and how accelerated particles escape into interplanetary space. While the fundamental building blocks of solar hard X-ray (HXR) focusing are in place and ready for a spacecraft mission, concurrent development is required to prepare for the next generation of high-energy solar explorers, which will require higher rate capability and higher angular resolution to investigate finer-scale structure and to better complement instruments at other wavelengths.

FOXSI-4 features technological advances that enable high angular resolution as well as measurement of bright sources. In the first category, we will develop high-precision mirror production methods and finely pixelated Si CMOS sensors, and will demonstrate substrip/subpixel resolution in fine-pitch CdTe sensors. Secondly, we will demonstrate rate capability of these sensors sufficient for flare measurement, and will develop novel pixelated attenuators that optimize energy coverage even at high rates.

The experiment will demonstrate these technologies in NASA's first-ever solar flare campaign, flying in tandem with the Hi-C FLARE rocket. The campaign will position multiple rocket experiments awaiting an opportunistic signal and will launch the experiments for near-simultaneous observation of the flare.This campaign will allow for direct collaboration with the Parker Solar Probe (PSP) during one of its perihelia. Title: Limits on the X-ray emission of the quiet Sun from the FOXSI sounding rockets Authors: Buitrago-Casas, J. C.; Glesener, L.; Christe, S.; Krucker, S.; Vievering, J. T.; Athiray, P. S.; Musset, S.; Ryan, D.; Ishikawa, S. N.; Narukage, N.; Bongiorno, S.; Furukawa, K.; Ramsey, B.; Davis, L.; Courtade, S.; Dalton, G.; Turin, P.; Turin, Z.; Takahashi, T.; Watanabe, S.; Mitsuishi, I.; Hagino, K.; Duncan, J. M. Bibcode: 2020AGUFMSH0430002B Altcode: Nanoflares are a potential solution for the coronal heating problem. In the quiet Sun, nanoflares should exhibit hard X-ray (HXR) signatures manifested to an observer via either i) a single HXR kernel or ii) HXRs from many flares spread all over the Sun. In both cases, detecting nanoflare HXRs requires an instrument with superior dynamic range and sensitivity in the ~4 to 15 keV energy range over previous solar dedicated HXR telescopes, like RHESSI. The Focusing Optics X-ray Solar Imager (FOXSI) fulfills these requirements. FOXSI has successfully flown on three sounding rocket campaigns; the last two (FOXSI-2 and -3) included the observation of quiet areas of the solar disk. For FOXSI-3, several techniques were tested and developed to minimize a background effect unique to hard X-ray focusing optics, frequently referred to as ghost rays.

In this presentation, we provide, for the first time, a FOXSI sounding rocket assessment of the HXR flux from the quiet Sun. To fully characterize the sensitivity of FOXSI, we assessed ghost rays generated by sources outside of the field of view via a ray-tracing algorithm. This is particularly important for observations from FOXSI-2 when techniques to minimize ghost rays were not implemented yet. Using the ray tracing tool, we identify areas free of ghost rays that contribute to the background and therefore have maximum sensitivity to quiet Sun HXR emission. We use a bayesian approach to provide upper thresholds of quiet Sun HXR emission and probability distributions for the expected flux when a quiet-Sun HXR source is assumed to exist. We compare this result with prior constraints such as that made by RHESSI (Hannah et al. 2010). Title: Use of a ray-tracing simulation to characterize ghost rays in the FOXSI rocket experiment Authors: Buitrago-Casas, J. C.; Christe, S.; Glesener, L.; Krucker, S.; Ramsey, B.; Bongiorno, S.; Kilaru, K.; Athiray, P. S.; Narukage, N.; Ishikawa, S.; Dalton, G.; Courtade, S.; Musset, S.; Vievering, J.; Ryan, D.; Bale, S. Bibcode: 2020JInst..15P1032B Altcode: 2020arXiv201007049B Imaging X-rays by direct focusing offers greater sensitivity and a higher dynamic range compared to techniques based on indirect imaging. The Focusing Optics X-ray Solar Imager (FOXSI) is a sounding rocket payload that uses seven sets of nested Wolter-I figured mirrors to observe the Sun in hard X-rays through direct focusing. Characterizing the performance of these optics is critical to optimize their performance and to understand their resulting data. In this paper, we present a ray-tracing simulation we created and developed to study Wolter-I X-ray mirrors. We validated the accuracy of the ray-tracing simulation by modeling the FOXSI rocket optics. We found satisfactory agreements between the simulation predictions and laboratory data measured on the optics. We used the ray-tracing simulation to characterize a background pattern of singly reflected rays (i.e., ghost rays) generated by photons at certain incident angles reflecting on only one of a two-segment Wolter-I figure and still reaching the focal plane. We used the results of the ray-tracing simulation to understand, and to formulate a set of strategies that can be used to mitigate, the impact of ghost rays on the FOXSI optical modules. These strategies include the optimization of aperture plates placed at the entrance and exit of the smallest Wolter-I mirror used in FOXSI, a honeycomb type collimator, and a wedge absorber placed at the telescope aperture. The ray-tracing simulation proved to be a reliable set of tools to study Wolter-I X-ray optics. It can be used in many applications, including astrophysics, material sciences, and medical imaging. Title: Inverse First Ionization Potential Effects in Giant Solar Flares Found from Earth X-Ray Albedo with Suzaku/XIS Authors: Katsuda, Satoru; Ohno, Masanori; Mori, Koji; Beppu, Tatsuhiko; Kanemaru, Yoshiaki; Tashiro, Makoto S.; Terada, Yukikatsu; Sato, Kosuke; Morita, Kae; Sagara, Hikari; Ogawa, Futa; Takahashi, Haruya; Murakami, Hiroshi; Nobukawa, Masayoshi; Tsunemi, Hiroshi; Hayashida, Kiyoshi; Matsumoto, Hironori; Noda, Hirofumi; Nakajima, Hiroshi; Ezoe, Yuichiro; Tsuboi, Yohko; Maeda, Yoshitomo; Yokoyama, Takaaki; Narukage, Noriyuki Bibcode: 2020ApJ...891..126K Altcode: 2020arXiv200110643K We report X-ray spectroscopic results for four giant solar flares that occurred on 2005 September 7 (X17.0), 2005 September 8 (X5.4), 2005 September 9 (X6.2), and 2006 December 5 (X9.0), obtained from Earth albedo data with the X-ray Imaging Spectrometer (XIS) on board Suzaku. The good energy resolution of the XIS (FWHM ∼ 100 eV) enables us to separate a number of line-like features and detect the underlying continuum emission. These features include Si Heα, Si Lyα, S Heα, S Lyα, Ar Heα, and Ca Heα originating from solar flares as well as fluorescent Ar Kα and Ar Kβ from the Earth's atmosphere. Absolute elemental abundances (X/H) averaged over the four flares are obtained to be ∼2.0 (Ca), ∼0.7 (Si), ∼0.3 (S), and ∼0.9 (Ar) at around flare peaks. This abundance pattern is similar to those of active stars' coronae showing inverse first ionization potential (I-FIP) effects, I.e., elemental abundances decrease with decreasing FIP with a turnover at the low end of the FIP. The abundances are almost constant during the flares, with the exception of Si which increases by a factor of ∼2 in the decay phase. The evolution of the Si abundance is consistent with the finding that the I-FIP plasma originates from chromospheric evaporation and then mixes with the surrounding low-FIP biased materials. Flare-to-flare abundance varied by a factor of two, agreeing with past observations of solar flares. Finally, we emphasize that Earth albedo data acquired by X-ray astronomy satellites like Suzaku and the X-Ray Imaging Spectroscopy Mission can significantly contribute to studies of solar physics. Title: FOXSI-2 Solar Microflares. I. Multi-instrument Differential Emission Measure Analysis and Thermal Energies Authors: Athiray, P. S.; Vievering, Juliana; Glesener, Lindsay; Ishikawa, Shin-nosuke; Narukage, Noriyuki; Buitrago-Casas, Juan Camilo; Musset, Sophie; Inglis, Andrew; Christe, Steven; Krucker, Säm; Ryan, Daniel Bibcode: 2020ApJ...891...78A Altcode: 2020arXiv200204200A In this paper we present the differential emission measures (DEMs) of two sub-A class microflares observed in hard X-rays (HXRs) by the FOXSI-2 sounding rocket experiment, on 2014 December 11. The second Focusing Optics X-ray Solar Imager (FOXSI) flight was coordinated with instruments X-ray Telescope (Hinode/XRT) and Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA), which provided observations in soft X-rays and Extreme Ultraviolet. This unique data set offers an unprecedented temperature coverage, useful for characterizing the plasma temperature distribution of microflares. By combining data from FOXSI-2, XRT, and AIA, we determined a well-constrained DEM for the microflares. The resulting DEMs peak around 3 MK and extend beyond 10 MK. The emission measures determined from FOXSI-2 were lower than 1026 cm-5 for temperatures higher than 5 MK; faint emission in this range is best measured in HXRs. The coordinated FOXSI-2 observations produce one of the few definitive measurements of the distribution and the amount of plasma above 5 MK in microflares. We utilize the multi-thermal DEMs to calculate the amount of thermal energy released during both the microflares as ∼5.0 × 1028 erg for Microflare 1 and ∼1.6 × 1028 erg for Microflare 2. We also show the multi-thermal DEMs provide more comprehensive thermal energy estimates than isothermal approximation, which systematically underestimates the amount of thermal energy released. Title: Estimating the Temperature and Density of a Spicule from 100 GHz Data Obtained with ALMA Authors: Shimojo, Masumi; Kawate, Tomoko; Okamoto, Takenori J.; Yokoyama, Takaaki; Narukage, Noriyuki; Sakao, Taro; Iwai, Kazumasa; Fleishman, Gregory D.; Shibata, Kazunari Bibcode: 2020ApJ...888L..28S Altcode: 2019arXiv191205714S We succeeded in observing two large spicules simultaneously with the Atacama Large Millimeter/submillimeter Array (ALMA), the Interface Region Imaging Spectrograph (IRIS), and the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory. One is a spicule seen in the IRIS Mg II slit-jaw images and AIA 304 Å images (Mg II/304 Å spicule). The other one is a spicule seen in the 100 GHz images obtained with ALMA (100 GHz spicule). Although the 100 GHz spicule overlapped with the Mg II/304 Å spicule in the early phase, it did not show any corresponding structures in the IRIS Mg II and AIA 304 Å images after the early phase. It suggests that the spicules are individual events and do not have a physical relationship. To obtain the physical parameters of the 100 GHz spicule, we estimate the optical depths as a function of temperature and density using two different methods. One is using the observed brightness temperature by assuming a filling factor, and the other is using an emission model for the optical depth. As a result of comparing them, the kinetic temperature of the plasma and the number density of ionized hydrogen in the 100 GHz spicule are ∼6800 K and 2.2 × 1010 cm-3. The estimated values can explain the absorbing structure in the 193 Å image, which appear as a counterpart of the 100 GHz spicule. These results suggest that the 100 GHz spicule presented in this Letter is classified to a macrospicule without a hot sheath in former terminology. Title: FOXSI-4: Instrument Upgrades for a Proposed Fourth Focusing Optics X-Ray Solar Imager Sounding Rocket Experiment Authors: Vievering, J. T.; Glesener, L.; Buitrago-Casas, J. C.; Panchapakesan, S. A.; Musset, S.; Duncan, J. M.; Narukage, N.; Ryan, D.; Inglis, A. R.; Takahashi, T.; Watanabe, S.; Christe, S.; Krucker, S.; Turin, P.; Ramsey, B. Bibcode: 2019AGUFMSH31C3315V Altcode: Observations of the Sun in hard X-rays can provide insight into many solar phenomena, including the mechanisms behind energy release and transport in flares. The indirect imaging methods used by RHESSI , the previous state-of-the-art solar hard X-ray instrument, however, were fundamentally limited in sensitivity and imaging dynamic range . By instead using the direct imaging technique of focusing hard X-rays, the structure and evolution of faint coronal sources, including microflares, active regions, and flare acceleration sites, can be investigated in greater depth. FOXSI ( Focusing Optics X-ray Solar Imager ), a hard X-ray instrument flown on three sounding rocket campaigns to date, seeks to achieve these improved capabilities by using focusing optics for solar observations in the 4-20 keV range. A fourth FOXSI sounding rocket experiment, FOXSI-4, has been proposed for launch in 2023, and the planned instrument upgrades are presented here. One main focus of FOXSI-4 will be to improve the angular resolution for solar hard X-ray instruments through the use of high-resolution optics, with the goal of reaching a half power diameter (HPD) of ∼5". Higher resolution will allow for individual footpoints and acceleration sites to be distinguished during a flare, which would benefit studies of the chromospheric response and provide constraints on flare acceleration mechanisms. FOXSI-4 will ideally be part of a flare campaign, in which multiple solar sounding rockets would be launched one after another to demonstrate the strength of new solar technologies when utilized in conjunction for flare observations. Title: Hardware upgrades and science outcomes from the latest flights of the FOXSI rocket Authors: Buitrago-Casas, J. C.; Glesener, L.; Courtade, S.; Vievering, J. T.; Athiray, P. S.; Musset, S.; Ryan, D.; Dalton, G.; Ishikawa, S. N.; Narukage, N.; Bongiorno, S.; Furukawa, K.; Davis, L.; Turin, P.; Turin, Z.; Takahashi, T.; Watanabe, S.; Krucker, S.; Christe, S.; Ramsey, B. Bibcode: 2019AGUFMSH31C3316B Altcode: FOXSI (which stands for the Focusing Optics X-ray Solar Imager) is a sounding rocket payload that has completed three successful flights supported by the Low-Cost Access to Space (LCAS) program of NASA. FOXSI stands out for being the first telescope optimized to use direct focusing to perform imaging spectroscopy of solar hard X-rays (HXRs). We present the latest instrument upgrades incorporated into the rocket payload for its third flight. We highlight the way these upgrades substantially improved the telescope performance and we present the observations obtained. Particularly, we describe the strategies implemented to reduce stray-light (ghost-ray) background and the inclusion of a soft X-ray CMOS sensor as well as HXR CdTe strip detectors to widen the spectral range of the telescope.

We finalize with an overview of the science results of the FOXSI flights. We present a differential emission measure (DEM) and thermal analyses of microflares observed during the second flight. We prove the relevance of the FOXSI measurements for obtaining unprecedented constrained microflare DEMs and discuss their implications on the energetics of these small flaring events. We finish presenting a discussion on the FOXSI measurements of an aged active region and quiet-sun areas observed during its latest flight. Title: Characterization of Charge Sharing in the FOXSI Sounding Rocket Hard X-ray Detectors Using the Advanced Light Source at Berkeley Authors: Duncan, J. M.; Panchapakesan, S. A.; Musset, S.; Vievering, J. T.; MacDowell, A. A.; Glesener, L.; Davis, L.; Buitrago-Casas, J. C.; O'Brien, C.; Ishikawa, S. N.; Takahashi, T.; Watanabe, S.; Narukage, N.; Furukawa, K.; Ryan, D.; Hagino, K.; Courtade, S.; Christe, S.; Krucker, S. Bibcode: 2019AGUFMSH31C3317D Altcode: The FOXSI sounding rocket experiments represent the first ever solar-dedicated direct-focusing hard X-ray (HXR) instruments. The most recent flight (FOXSI-3) occurred in September 2018, utilizing Wolter-1 style concentric-shell optics and both silicon (Si) and cadmium telluride (CdTe) double-sided strip detectors. The angular resolution of the optics (5" FWHM, equivalent to 50um at the detector bench) is finer than the strip pitch of the Si and CdTe detectors (75um and 60um, respectively), meaning that the resolution of the instrument at sounding rocket focal lengths is detector-limited [1]. In order to further improve characterization of the spatial and spectral properties of the FOXSI-3 detectors, experiments were recently completed using Beamline 3.3.2. at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. Using this beamline, a fine (2um x 2um or 5um x 5um) monoenergetic x-ray beam was scanned across detector strips and inter-strip regions in steps much smaller than the strip pitch. Such scans were performed for both Si and CdTe detectors at a number of x-ray energies between 5.5-12 keV. These experiments were particularly motivated by the desire to measure the incidence of charge sharing, which occurs when a single incident photon causes signals to be registered in multiple adjacent strips. Precise measurement of charge sharing behavior is important to optimize characterization of detector efficiency. Additionally, with a strong understanding of charge sharing behavior in a detector, spatial resolution could be improved by sub-strip localization of photon impacts. Here, we present initial analysis of results from these ALS experiments, including investigation into charge sharing properties in both the Si and CdTe FOXSI-3 detectors. We also discuss the implications of these results for the use of these detectors in the future FOXSI-4 mission, which will utilize yet-higher-resolution HXR optics.

[1] Furukawa,K.,et al. "Development of 60um pitch CdTe Double-sided Strip Detectors for the FOXSI-3 sounding rocket experiment." NIMPR, Section A: HSTD11, 2017. Title: High-frequency Wave Propagation Along a Spicule Observed by CLASP Authors: Yoshida, Masaki; Suematsu, Yoshinori; Ishikawa, Ryohko; Okamoto, Takenori J.; Kubo, Masahito; Kano, Ryouhei; Narukage, Noriyuki; Bando, Takamasa; Winebarger, Amy R.; Kobayashi, Ken; Trujillo Bueno, Javier; Auchère, Frédéric Bibcode: 2019ApJ...887....2Y Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) sounding rocket experiment, launched in 2015 September, observed the hydrogen Lyα line (121.6 nm) in an unprecedented high temporal cadence of 0.3 s. CLASP performed sit-and-stare observations of the quiet Sun near the limb for 5 minutes with a slit perpendicular to the limb and successfully captured an off-limb spicule evolving along the slit. The Lyα line is well suited for investigating how spicules affect the corona because it is sensitive to higher temperatures than other chromospheric lines, owing to its large optical thickness. We found high-frequency oscillations of the Doppler velocity with periods of 20-50 s and low-frequency oscillation of periods of ∼240 s on the spicule. From a wavelet analysis of the time sequence data of the Doppler velocity, in the early phase of the spicule evolution, we found that waves with a period of ∼30 s and a velocity amplitude of 2-3 km s-1 propagated upward along the spicule with a phase velocity of ∼470 km s-1. In contrast, in the later phase, possible downward and standing waves with smaller velocity amplitudes were also observed. The high-frequency waves observed in the early phase of the spicule evolution would be related with the dynamics and the formation of the spicules. Our analysis enabled us to identify the upward, downward, and standing waves along the spicule and to obtain the velocity amplitude of each wave directly from the Doppler velocity for the first time. We evaluated the energy flux by the upward-propagating waves along the spicule, and discussed the impact to the coronal heating. Title: Satellite mission: PhoENiX (Physics of Energetic and Non-thermal plasmas in the X (= magnetic reconnection) region) Authors: Narukage, N. Bibcode: 2019AGUFMSH31C3311N Altcode: We are planning a new solar satellite mission, "PhoENiX", for understanding of particle acceleration during magnetic reconnection. The main observation targets of this mission are solar flares, which are generated by magnetic reconnection and accelerate plasma particles.

The scientific objectives of this mission are (1) to identify particle acceleration sites, (2) to investigate temporal evolution of particle acceleration, and (3) to characterize properties of accelerated particles, during solar flares. In order to achieve these science objectives, the PhoENiX satellite is planned to be equipped with three instruments of (1) Photon-counting type focusing-imaging spectrometer in soft X-rays (up to ~10 keV) to observe the contexts of particle accelerations (e.g., shocks, plasmoids, flows, etc.), (2) Photon-counting type focusing-imaging spectrometer in hard X-rays (up to ~30 keV) to identify the accelerated particles, and (3) Spectropolarimeter in soft gamma-rays (spectroscopy is available in the energy range of from > 20 keV to < 600 keV; spectropolarimetry is available from > 60 keV to < 600 keV) to detect the anisotropy of accelerated particles. We plan to realize the PhoENiX satellite mission around next solar maximum (around 2025).

The basic developments of key technologies for these instruments have been completed. The soft X-ray imaging spectroscopy is planned to be realized with the combination of high-precision glass-polished X-ray mirrors and high-speed CMOS cameras. The hard X-ray imaging spectroscopy consists of high-precision electroforming X-ray mirrors and CdTe cameras. The soft gamma-ray spectropolarimeter is a redesigned instrument of Hitomi / Soft Gamma-ray Detector (SGD) that has Compton cameras with active shields. Some of these technologies have been demonstrated by FOXSI sounding rocket series launched in 2012, 2014 and 2018. The 4th flight of FOXSI sounding rocket is being proposed for the X-ray imaging spectroscopic observation of the solar flare with high spatial resolution. This is a good opportunity to demonstrate the PhoENiX satellite in the both point of views of science and technology. In this presentation, we explain the details of science goal and objectives, and instruments of the PhoENiX mission. Title: The Solar High-Resolution X-ray imager (SHRX): A Concept for a Sounding Rocket Experiment Authors: Champey, P. R.; Savage, S. L.; Winebarger, A. R.; Broadway, D.; Kobayashi, K.; Davis, J.; Kolodziejczak, J.; Griffith, C.; Narukage, N. Bibcode: 2019AGUFMSH31C3318C Altcode: The evolution and spatial distribution of small-scale, high-temperature plasma structures in the solar corona can be used to address multiple open science questions, including how the corona is dynamically heated, and how tremendous amounts of energy are released within seconds during eruptive events. Despite decades of imaging this plasma in X-rays, the spatial resolution of available grazing incidence mirrors has constrained our understanding of this important energy regime. High temperature plasma can be imaged in the extreme ultraviolet (EUV) using normal incidence telescopes, which can be more-readily fabricated to meet high resolution requirements. Multi-layers can be implemented to limit the narrow passband to select for EUV wavelengths containing high temperature emission lines. The EUV spectrum, however, contains cooler emission lines that inevitably contaminate high temperature channels. Here, we present a design concept for a high-resolution, (< 1 arcsecond) soft X-ray (SXR) imager to fly aboard a sounding rocket that will enable solar observations of small-scale structures containing plasma greater than 5 million degrees. The Solar High Resolution X-ray imager (SHRX) will observe a narrow SXR band centered at 1.03 keV (12 Angstroms) using cutting-edge multi-layer coatings and an improved glass substrate grazing incidence mirror developed at NASA Marshall Space Flight Center (MSFC). The optical design accommodates a CMOS detector developed by the Japan Aerospace Exploration Agency (JAXA), and previously flown aboard the FOXSI-3 sounding rocket. The detector consists of a 2k X 2k chip, 7 micron square pixel size, and rapid readout time enabling photon-counting capability. The science objective is to study small-scale, active region plasma flows associated with dynamic energy release. Within the constraints of a sounding rocket experiment, this will be accomplished via sub-arcsecond SXR observations of active region core plasma in a bandpass that overlaps with the temperature responses of Hinode/XRT and the SDO/AIA 94Å channel. The effective area curve of the mirror will be tuned via the mirror prescription and the multi-layer coating, which will shape the temperature response of the instrument. Here we present our science objectives and a technical overview of the instrument concept. Title: Ghost-ray reduction and early results from the third FOXSI sounding rocket flight Authors: Musset, Sophie; Buitrago-Casas, Juan Camilo; Glesener, Lindsay; Bongiorno, Stephen; Courtade, Sasha; Athiray, P. S.; Vievering, Juliana; Ishikawa, Shin-nosuke; Narukage, Noriyuki; Furukawa, Kento; Ryan, Daniel; Dalton, Greg; Turin, Zoe; Davis, Lance; Takahashi, Tadayuki; Watanabe, Shin; Mitsuishi, Ikuyuki; Hagino, Kouichi; Kawate, Tomoko; Turin, Paul; Christe, Steven; Ramsey, Brian; Krucker, Säm. Bibcode: 2019SPIE11118E..12M Altcode: The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment demonstrates the technique of focusing hard X-ray (HXR) optics for the study of fundamental questions about the high-energy Sun. Solar HXRs provide one of the most direct diagnostics of accelerated electrons and the impulsive heating of the solar corona. Previous solar missions have been limited in sensitivity and dynamic range by the use of indirect imaging, but technological advances now make direct focusing accessible in the HXR regime, and the FOXSI rocket experiment optimizes HXR focusing telescopes for the unique scientific requirements of the Sun. FOXSI has completed three successful flights between 2012 and 2018. This paper gives a brief overview of the experiment, focusing on the third flight of the instrument on 2018 Sept. 7. We present the telescope upgrades highlighting our work to understand and reduce the effects of singly reflected X-rays and show early science results obtained during FOXSI's third flight. Title: The FOXSI-3 rocket: Overview and early results of its latest flight Authors: Buitrago-Casas, Juan Camilo; Glesener, Lindsay; Courtade, Sasha; Vievering, Juliana; Athiray Panchapakesan, Subramania; Musset, Sophie; Ryan, Daniel; Dalton, Gregory; Ishikawa, Shin-Nosuke; Narukage, Noriyuki; Bongiorno, Stephen; Furukawa, Kento; Davis, Lance; Turin, Paul; Turin, Zoe; Takahashi, Tadayuki; Watanabe, Shin; Krucker, Sam; Christe, Steven; Ramsey, Brian Bibcode: 2019AAS...23412602B Altcode: Hard X-rays (HXRs) from the solar corona are closely connected to energy releases and particle transport in solar flares of all sizes. Expressly, faint solar HXR emissions are of remarkable interest in understanding solar flare structure and dynamics. This is because of their connection with, for instance, loop top emission and small flares. Mainly due to the indirect imaging methods used by past solar-dedicated HXR imagers, like RHESSI, faint HXRs observations have been limited by the imaging dynamic range and sensitivity of the instruments.

The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket payload is the first solar-dedicated instrument designed for performing imaging spectroscopy in the 4-20 keV range by using direct focusing optics. FOXSI has successfully flown three times from the White Sands Missile Range in New Mexico. For its latest rocket campaign (FOXSI-3), an enhanced version of the experiment, which includes optics and detector upgrades, was implemented for the launch which happened on September 7, 2018. In this talk, we present an overview of the FOXSI-3 campaign, describing in detail the improved capabilities of the telescope and how they allow for better investigation of faint coronal HXRs. We also present a preliminary analysis of the FOXSI-3 observations. Title: FOXSI-2 Solar Microflares : Multi-Instrument Differential Emission Measure Analysis Authors: Athiray, P. S.; Glesener, Lindsay; Vievering, Juliana; Ishikawa, Shin-Nosuke; Inglis, Andrew; Narukage, Noriyuki; Ryan, Daniel; Buitrago-Casas, Juan Camilo; Christe, Steven; Musset, Sophie; Krucker, Sam Bibcode: 2019AAS...23422502A Altcode: The plasma temperature distribution above 5 MK during microflares is often loosely constrained due to limited high sensitivity hard X-ray measurements covering the wide range of temperatures observed. The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket experiment performs direct imaging and spectroscopy of the Sun in hard X-rays, in the energy range 4 to 20 keV. FOXSI offers better sensitivity for temperatures above 5 MK by using direct focusing grazing incidence X-ray optics, the first of its kind for dedicated solar observations. The second FOXSI flight was launched on 2014 December 11 and observed microflares, quiescent Sun and quiescent active regions. This flight was coordinated with the X-ray Telescope (XRT) onboard Hinode and the Atmospheric Imaging Assembly (AIA) onboard SDO which offers unprecedented temperature coverage for characterizing the plasma temperature distribution. We present an overview of microflares observed during the FOXSI-2 flight with concurrent brightening observed in Extreme Ultraviolet (EUV) and soft X-rays, which indicates emission beyond 10 MK. By combining data from FOXSI-2, XRT, and AIA, we determined a well-constrained DEM for the microflares. The coordinated FOXSI-2 observations produce one of the few definitive measurements of the distribution and the amount of plasma above 5 MK in microflares. Title: Satellite mission: PhoENiX (Physics of Energetic and Non-thermal plasmas in the X (= magnetic reconnection) region) Authors: Narukage, Noriyuki Bibcode: 2019AAS...23412603N Altcode: We are studying a new solar satellite mission, "PhoENiX", for understanding of particle acceleration during magnetic reconnection, which are ubiquitous features exhibited by a wide range of plasmas in the universe. The main observation targets of this mission are solar flares that are caused by magnetic reconnection and accelerate plasma particles. The sun is a unique target in the sense that it can be investigated in great detail with good spatial, temporal and energy resolutions. The scientific objectives of this mission are (1) to identify particle acceleration sites, (2) to investigate temporal evolution of particle acceleration, and (3) to characterize properties of accelerated particles, during magnetic reconnection, i.e., during solar flares. In order to achieve these science objectives, the PhoENiX satellite is planned to be equipped with three instruments of (1) Photon-counting type focusing-imaging spectrometer in soft X-rays (up to 10 keV) demonstrated by FOXSI-3, (2) Photon-counting type focusing-imaging spectrometer in hard X-rays (up to 30 keV) like FOXSI series, and (3) Spectropolarimeter in soft gamma-rays (spectroscopy is available in the energy range of from > 20 keV to < 600 keV; spectropolarimetry is available from > 60 keV to < 600 keV) like Hitomi/SGD. We plan to realize this satellite mission around next solar maximum (around 2025). In this presentation, we will explain the details of science goal, science objectives and instruments of PhoENiX mission. Additionally, in order to demonstrate the unprecedented observations with PhoENiX, we will show the soft X-ray photon-counting data taken by FOXSI-3 sounding rocket. Title: Modeling the Scattering Polarization of the Hydrogen Lyα Line Observed by CLASP in a Filament Channel Authors: Štěpán, J.; Trujillo Bueno, J.; Gunár, S.; Heinzel, P.; del Pino Alemán, T.; Kano, R.; Ishikawa, R.; Narukage, N.; Bando, T.; Winebarger, A.; Kobayashi, K.; Auchère, F. Bibcode: 2019ASPC..526..165S Altcode: The 400 arcsec spectrograph slit of CLASP crossed mainly quiet regions of the solar chromosphere, from the limb towards the solar disk center. Interestingly, in the CLASP slit-jaw images and in the SDO images of the He II line at 304 Å, we can identify a filament channel (FC) extending over more than 60 arcsec crossing the slit of the spectrograph. In order to interpret the peculiar spatial variation of the Q/I and U/I signals observed by CLASP in the hydrogen Lyα line (1216 Å), we perform multi-dimensional radiative transfer modeling in given filament models. In this contribution, we show the first results of the two-dimensional calculations we have carried out, with the aim of determining the filament thermal and magnetic structure by comparing the theoretical and the observed polarization signals. Our results suggest that the temperature gradients in the filament observed by CLASP are significantly larger than previously thought. Title: CLASP2: The Chromospheric LAyer Spectro-Polarimeter Authors: McKenzie, D. E.; Ishikawa, R.; Trujillo Bueno, J.; Auchére, F.; Rachmeler, L. A.; Kubo, M.; Kobayashi, K.; Winebarger, A. R.; Bethge, C. W.; Narukage, N.; Kano, R.; Ishikawa, S.; de Pontieu, B.; Carlsson, M.; Yoshida, M.; Belluzzi, L.; Štěpán, J.; del Pino Alemán, T.; Alsina Ballester, E.; Asensio Ramos, A. Bibcode: 2019ASPC..526..361M Altcode: The hydrogen Lyman-α line at 121.6 nm and the Mg k line at 279.5 nm are especially relevant for deciphering the magnetic structure of the chromosphere since their line-center signals are formed in the chromosphere and transition region, with unique sensitivities to magnetic fields. We propose the Chromospheric LAyer Spectro-Polarimeter (CLASP2), to build upon the success of the first CLASP flight, which measured the linear polarization in H I Lyman-α. The existing CLASP instrument will be refitted to measure all four Stokes parameters in the 280 nm range, including variations due to the anisotropic radiation pumping, the Hanle effect, and the Zeeman effect. Title: Comparison of Scattering Polarization Signals Observed by CLASP: Possible Indication of the Hanle Effect Authors: Ishikawa, R.; Trujillo Bueno, J.; Uitenbroek, H.; Kubo, M.; Tsuneta, S.; Goto, M.; Kano, R.; Narukage, N.; Bando, T.; Katsukawa, Y.; Ishikawa, S.; Giono, G.; Suematsu, Y.; Hara, H.; Shimizu, T.; Sakao, T.; Winebarger, A.; Kobayashi, K.; Cirtain, J.; Champey, P.; Auchère, F.; Štěpán, J.; Belluzzi, L.; Asensio Ramos, A.; Manso Sainz, R.; De Pomtieu, B.; Ichimoto, K.; Carlsson, M.; Casini, R. Bibcode: 2019ASPC..526..305I Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP; Kano et al. 2012; Kobayashi et al. 2012; Kubo et al. 2014) observed, for the first time, the linear polarization produced by scattering processes in the hydrogen Lyman-α (121.57 nm) and Si III (120.56 nm) lines of the solar disk radiation. The complexity of the observed scattering polarization (i.e., conspicuous spatial variations in Q/I and U/I at spatial scales of 10″-20″ and the absence of center-to- limb variation at the Lyman-α center; see Kano et al. 2017) motivated us to search for possible hints of the operation of the Hanle effect by comparing: (a) the Lyman-α line center signal, for which the critical field strength (BH) for the onset of the Hanle effect is 53 G, (b) the Lyman-α wing, which is insensitive to the Hanle effect, and (c) the Si III line, whose BH = 290 G. We focus on four regions with different total unsigned photospheric magnetic fluxes (estimated from SDO/HMI observations), and compare the corresponding U/I spatial variations in the Lyman-α wing, Lyman-α center, and Si III line. The U/I signal in the Lyman-α wing shows an antisymmetric spatial distribution, which is caused by the presence of a bright structure in all the selected regions, regardless of the total unsigned photospheric magnetic flux. In an internetwork region, the Lyman-α center shows an antisymmetric spatial variation across the selected bright structure, but it does not show it in other more magnetized regions. In the Si III line, the spatial variation of U/I deviates from the above-mentioned antisymmetric shape as the total unsigned photospheric magnetic flux increases. We argue that a plausible explanation of this differential behavior is the operation of the Hanle effect.

This work, presented in an oral contribution at this Workshop, has been published on The Astrophysical Journal (Ishikawa et al. 2017). Title: High-speed X-ray imaging spectroscopy system with Zynq SoC for solar observations Authors: Ishikawa, Shin-nosuke; Takahashi, Tadayuki; Watanabe, Shin; Narukage, Noriyuki; Miyazaki, Satoshi; Orita, Tadashi; Takeda, Shin'ichiro; Nomachi, Masaharu; Fujishiro, Iwao; Hodoshima, Fumio Bibcode: 2018NIMPA.912..191I Altcode: 2017arXiv171104372I We have developed a system combining a back-illuminated Complementary-Metal-Oxide-Semiconductor (CMOS) imaging sensor and Xilinx Zynq System-on-Chip (SoC) device for a soft X-ray (0.5-10 keV) imaging spectroscopy observation of the Sun to investigate the dynamics of the solar corona. Because typical timescales of energy release phenomena in the corona span a few minutes at most, we aim to obtain the corresponding energy spectra and derive the physical parameters, i.e., temperature and emission measure, every few tens of seconds or less for future solar X-ray observations. An X-ray photon-counting technique, with a frame rate of a few hundred frames per second or more, can achieve such results. We used the Zynq SoC device to achieve the requirements. Zynq contains an ARM processor core, which is also known as the Processing System (PS) part, and a Programable Logic (PL) part in a single chip. We use the PL and PS to control the sensor and seamless recording of data to a storage system, respectively. We aim to use the system for the third flight of the Focusing Optics Solar X-ray Imager (FOXSI-3) sounding rocket experiment for the first photon-counting X-ray imaging and spectroscopy of the Sun. Title: CLASP Constraints on the Magnetization and Geometrical Complexity of the Chromosphere-Corona Transition Region Authors: Trujillo Bueno, J.; Štěpán, J.; Belluzzi, L.; Asensio Ramos, A.; Manso Sainz, R.; del Pino Alemán, T.; Casini, R.; Ishikawa, R.; Kano, R.; Winebarger, A.; Auchère, F.; Narukage, N.; Kobayashi, K.; Bando, T.; Katsukawa, Y.; Kubo, M.; Ishikawa, S.; Giono, G.; Hara, H.; Suematsu, Y.; Shimizu, T.; Sakao, T.; Tsuneta, S.; Ichimoto, K.; Cirtain, J.; Champey, P.; De Pontieu, B.; Carlsson, M. Bibcode: 2018ApJ...866L..15T Altcode: 2018arXiv180908865T The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a suborbital rocket experiment that on 2015 September 3 measured the linear polarization produced by scattering processes in the hydrogen Lyα line of the solar disk radiation. The line-center photons of this spectral line radiation mostly stem from the chromosphere-corona transition region (TR). These unprecedented spectropolarimetric observations revealed an interesting surprise, namely that there is practically no center-to-limb variation (CLV) in the Q/I line-center signals. Using an analytical model, we first show that the geometric complexity of the corrugated surface that delineates the TR has a crucial impact on the CLV of the Q/I and U/I line-center signals. Second, we introduce a statistical description of the solar atmosphere based on a 3D model derived from a state-of-the-art radiation magnetohydrodynamic simulation. Each realization of the statistical ensemble is a 3D model characterized by a given degree of magnetization and corrugation of the TR, and for each such realization we solve the full 3D radiative transfer problem taking into account the impact of the CLASP instrument degradation on the calculated polarization signals. Finally, we apply the statistical inference method presented in a previous paper to show that the TR of the 3D model that produces the best agreement with the CLASP observations has a relatively weak magnetic field and a relatively high degree of corrugation. We emphasize that a suitable way to validate or refute numerical models of the upper solar chromosphere is by confronting calculations and observations of the scattering polarization in ultraviolet lines sensitive to the Hanle effect. Title: A Statistical Inference Method for Interpreting the CLASP Observations Authors: Štěpán, J.; Trujillo Bueno, J.; Belluzzi, L.; Asensio Ramos, A.; Manso Sainz, R.; del Pino Alemán, T.; Casini, R.; Kano, R.; Winebarger, A.; Auchère, F.; Ishikawa, R.; Narukage, N.; Kobayashi, K.; Bando, T.; Katsukawa, Y.; Kubo, M.; Ishikawa, S.; Giono, G.; Hara, H.; Suematsu, Y.; Shimizu, T.; Sakao, T.; Tsuneta, S.; Ichimoto, K.; Cirtain, J.; Champey, P.; De Pontieu, B.; Carlsson, M. Bibcode: 2018ApJ...865...48S Altcode: 2018arXiv180802725S On 2015 September 3, the Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) successfully measured the linear polarization produced by scattering processes in the hydrogen Lyα line of the solar disk radiation, revealing conspicuous spatial variations in the Q/I and U/I signals. Via the Hanle effect, the line-center Q/I and U/I amplitudes encode information on the magnetic field of the chromosphere-corona transition region, but they are also sensitive to the three-dimensional structure of this corrugated interface region. With the help of a simple line-formation model, here we propose a statistical inference method for interpreting the Lyα line-center polarization observed by CLASP. Title: Current State of UV Spectro-Polarimetry and its Future Direction Authors: Ishikawa, Ryohko; Sakao, Taro; Katsukawa, Yukio; Hara, Hirohisa; Ichimoto, Kiyoshi; Shimizu, Toshifumi; Kubo, Masahito; Auchere, Frederic; De Pontieu, Bart; Winebarger, Amy; Kobayashi, . Ken; Kano, Ryouhei; Narukage, Noriyuki; Trujillo Bueno, Javier; Song, Dong-uk; Manso Sainz, Rafael; Asensio Ramos, Andres; Leenaarts, Jorritt; Carlsson, Mats; Bando, Takamasa; Ishikawa, Shin-nosuke; Tsuneta, Saku; Belluzzi, Luca; Suematsu, Yoshinori; Giono, Gabriel; Yoshida, Masaki; Goto, Motoshi; Del Pino Aleman, Tanausu; Stepan, Jiri; Okamoto, Joten; Tsuzuki, Toshihiro; Uraguchi, Fumihiro; Champey, Patrick; Alsina Ballester, Ernest; Casini, Roberto; McKenzie, David; Rachmeler, Laurel; Bethge, Christian Bibcode: 2018cosp...42E1564I Altcode: To obtain quantitative information on the magnetic field in low beta regions (i.e., upper chromosphere and above) has been increasingly important to understand the energetic phenomena of the outer solar atmosphere such as flare, coronal heating, and the solar wind acceleration. In the UV range, there are abundant spectral lines that originate in the upper chromosphere and transition region. However, the Zeeman effect in these spectral lines does not give rise to easily measurable polarization signals because of the weak magnetic field strength and the larger Doppler broadening compared with the Zeeman effect. Instead, the Hanle effect in UV lines is expected to be a suitable diagnostic tool of the magnetic field in the upper atmospheric layers. To investigate the validity of UV spectro-polarimetry and the Hanle effect, the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP), which is a NASA sounding- rocket experiment, was launched at White Sands in US on September 3, 2015. During its 5 minutes ballistic flight, it successfully performed spectro-polarimetric observations of the hydrogen Lyman-alpha line (121.57 nm) with an unprecedentedly high polarization sensitivity of 0.1% in this wavelength range. CLASP observed the linear polarization produced by scattering process in VUV lines for the first time and detected the polarization signals which indicate the operation of the Hanle effect. Following the success of CLASP, we are confident that UV spectro-polarimetry is the way to proceed, and we are planning the second flight of CLASP (CLASP2: Chromospheric LAyer SpectroPolarimeter 2). For this second flight we will carry out spectro-polarimetry in the Mg II h and k lines around 280 nm, with minimum modifications of the CLASP1 instrument. The linear polarization in the Mg II k line is induced by scattering processes and the Hanle effect, being sensitive to magnetic field strengths of 5 to 50 G. In addition, the circular polarizations in the Mg II h and k lines induced by the Zeeman effect can be measurable in at least plage and active regions. The combination of the Hanle and Zeeman effects could help us to more reliably infer the magnetic fields of the upper solar chromosphere. CLASP2 was selected for flight and is being developed for launch in the spring of 2019.Based on these sounding rocket experiments (CLASP1 and 2), we aim at establishing the strategy and refining the instrument concept for future space missions to explore the enigmatic atmospheric layers via UV spectro-polarimetry. Title: Wavefront error measurements and alignment of CLASP2 telescope with a dual-band pass cold mirror coated primary mirror Authors: Yoshida, Masaki; Song, Donguk; Ishikawa, Ryoko; Kano, Ryouhei; Katsukawa, Yukio; Suematsu, Yoshinori; Narukage, Noriyuki; Kubo, Masahito; Shinoda, Kazuya; Okamoto, Takenori J.; McKenzie, David E.; Rachmeler, Laurel A.; Auchère, Frédéric; Trujillo Bueno, Javier Bibcode: 2018SPIE10699E..30Y Altcode: "Chromospheric LAyer Spectro-Polarimeter (CLASP2)" is the next sounding rocket experiment of the "Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP)" that succeeded in observing for the first time the linear polarization spectra in the hydrogen Lyman-α line (121.6 nm) and is scheduled to be launched in 2019. In CLASP2, we will carry out full Stokes-vector spectropolarimetric observations in the Mg ii h and k lines near 280 nm with the spectro-polarimeter (SP), while imaging observations in the Lyman-α line will be conducted with the slitjaw optics (SJ). For the wavelength selection of CLASP2, the primary mirror of the telescope uses a new dual-band pass cold mirror coating targeting both at 121.6 nm and 280 nm. Therefore, we have to perform again the alignment of the telescope after the installation of the recoated primary mirror. Before unmounting the primary mirror from the telescope structure, we measured the wave-front error (WFE) of the telescope. The measured WFE map was consistent with what we had before the CLASP flight, clearly indicating that the telescope alignment has been maintained even after the flight. After the re-coated primary mirror was installed the WFE was measured, and coma aberration was found to be larger. Finally, the secondary mirror shim adjustments were carried out based on the WFE measurements. In CLASP2 telescope, we improved a fitting method of WFE map (applying 8th terms circular Zernike polynomial fitting instead of 37th terms circular Zernike fitting) and the improved method enables to achieve better performance than CLASP telescope. Indeed, WFE map obtained after the final shim adjustment indicated that the required specification (< 5.5 μm RMS spot radius) that is more stringent than CLASP telescope was met. Title: Detection of nanoflare-heated plasma in the solar corona by the FOXSI-2 sounding rocket Authors: Ishikawa, Shin-nosuke; Glesener, Lindsay; Krucker, Säm; Christe, Steven; Buitrago-Casas, Juan Camilo; Narukage, Noriyuki; Vievering, Juliana Bibcode: 2017NatAs...1..771I Altcode: The processes that heat the solar and stellar coronae to several million kelvins, compared with the much cooler photosphere (5,800 K for the Sun), are still not well known1. One proposed mechanism is heating via a large number of small, unresolved, impulsive heating events called nanoflares2. Each event would heat and cool quickly, and the average effect would be a broad range of temperatures including a small amount of extremely hot plasma. However, detecting these faint, hot traces in the presence of brighter, cooler emission is observationally challenging. Here we present hard X-ray data from the second flight of the Focusing Optics X-ray Solar Imager (FOXSI-2), which detected emission above 7 keV from an active region of the Sun with no obvious individual X-ray flare emission. Through differential emission measure computations, we ascribe this emission to plasma heated above 10 MK, providing evidence for the existence of solar nanoflares. The quantitative evaluation of the hot plasma strongly constrains the coronal heating models. Title: Comparison of Solar Fine Structure Observed Simultaneously in Lyα and Mg II h Authors: Schmit, D.; Sukhorukov, A. V.; De Pontieu, B.; Leenaarts, J.; Bethge, C.; Winebarger, A.; Auchère, F.; Bando, T.; Ishikawa, R.; Kano, R.; Kobayashi, K.; Narukage, N.; Trujillo Bueno, J. Bibcode: 2017ApJ...847..141S Altcode: 2017arXiv170900035S The Chromospheric Lyman Alpha Spectropolarimeter (CLASP) observed the Sun in H I Lyα during a suborbital rocket flight on 2015 September 3. The Interface Region Imaging Telescope (IRIS) coordinated with the CLASP observations and recorded nearly simultaneous and co-spatial observations in the Mg II h and k lines. The Mg II h and Lyα lines are important transitions, energetically and diagnostically, in the chromosphere. The canonical solar atmosphere model predicts that these lines form in close proximity to each other and so we expect that the line profiles will exhibit similar variability. In this analysis, we present these coordinated observations and discuss how the two profiles compare over a region of quiet Sun at viewing angles that approach the limb. In addition to the observations, we synthesize both line profiles using a 3D radiation-MHD simulation. In the observations, we find that the peak width and the peak intensities are well correlated between the lines. For the simulation, we do not find the same relationship. We have attempted to mitigate the instrumental differences between IRIS and CLASP and to reproduce the instrumental factors in the synthetic profiles. The model indicates that formation heights of the lines differ in a somewhat regular fashion related to magnetic geometry. This variation explains to some degree the lack of correlation, observed and synthesized, between Mg II and Lyα. Our analysis will aid in the definition of future observatories that aim to link dynamics in the chromosphere and transition region. Title: CLASP/SJ Observations of Rapid Time Variations in the Lyα Emission in a Solar Active Region Authors: Ishikawa, Shin-nosuke; Kubo, Masahito; Katsukawa, Yukio; Kano, Ryouhei; Narukage, Noriyuki; Ishikawa, Ryohko; Bando, Takamasa; Winebarger, Amy; Kobayashi, Ken; Trujillo Bueno, Javier; Auchère, Frédéric Bibcode: 2017ApJ...846..127I Altcode: The Chromospheric Lyα SpectroPolarimeter (CLASP) is a sounding rocket experiment launched on 2015 September 3 to investigate the solar chromosphere and transition region. The slit-jaw (SJ) optical system captured Lyα images with a high time cadence of 0.6 s. From the CLASP/SJ observations, many variations in the solar chromosphere and transition region emission with a timescale of <1 minute were discovered. In this paper, we focus on the active region within the SJ field of view and investigate the relationship between short (<30 s) temporal variations in the Lyα emission and the coronal structures observed by Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA). We compare the Lyα temporal variations at the coronal loop footpoints observed in the AIA 211 Å (≈2 MK) and AIA 171 Å (≈0.6 MK) channels with those in the regions with bright Lyα features without a clear association with the coronal loop footpoints. We find more short (<30 s) temporal variations in the Lyα intensity in the footpoint regions. Those variations did not depend on the temperature of the coronal loops. Therefore, the temporal variations in the Lyα intensity at this timescale range could be related to the heating of the coronal structures up to temperatures around the sensitivity peak of 171 Å. No signature was found to support the scenario that these Lyα intensity variations were related to the nanoflares. Waves or jets from the lower layers (lower chromosphere or photosphere) are possible causes for this phenomenon. Title: Methods for reducing singly reflected rays on the Wolter-I focusing mirrors of the FOXSI rocket experiment Authors: Buitrago-Casas, Juan Camilo; Elsner, Ronald; Glesener, Lindsay; Christe, Steven; Ramsey, Brian; Courtade, Sasha; Ishikawa, Shin-nosuke; Narukage, Noriyuki; Turin, Paul; Vievering, Juliana; Athiray, P. S.; Musset, Sophie; Krucker, Säm. Bibcode: 2017SPIE10399E..0JB Altcode: In high energy solar astrophysics, imaging hard X-rays by direct focusing offers higher dynamic range and greater sensitivity compared to past techniques that used indirect imaging. The Focusing Optics X-ray Solar Imager (FOXSI) is a sounding rocket payload that uses seven sets of nested Wolter-I figured mirrors together with seven high-sensitivity semiconductor detectors to observe the Sun in hard X-rays through direct focusing. The FOXSI rocket has successfully flown twice and is funded to fly a third time in summer 2018. The Wolter-I geometry consists of two consecutive mirrors, one paraboloid and one hyperboloid, that reflect photons at grazing angles. Correctly focused X-rays reflect once per mirror segment. For extended sources, like the Sun, off-axis photons at certain incident angles can reflect on only one mirror and still reach the focal plane, generating a background pattern of singly reflected rays (i.e., ghost rays) that can limit the sensitivity of the observation to faint, focused sources. Understanding and mitigating the impact of the singly reflected rays on the FOXSI optical modules will maximize the instruments' sensitivity to background-limited sources. We present an analysis of the FOXSI singly reflected rays based on ray-tracing simulations and laboratory measurements, as well as the effectiveness of different physical strategies to reduce them. Title: Detection of Heating Processes in Coronal Loops by Soft X-ray Spectroscopy Authors: Kawate, Tomoko; Narukage, Noriyuki; Ishikawa, Shin-nosuke; Imada, Shinsuke Bibcode: 2017SPD....4810615K Altcode: Imaging and Spectroscopic observations in the soft X-ray band will open a new window of the heating/acceleration/transport processes in the solar corona. The soft X-ray spectrum between 0.5 and 10 keV consists of the electron thermal free-free continuum and hot coronal lines such as O VIII, Fe XVII, Mg XI, Si XVII. Intensity of free-free continuum emission is not affected by the population of ions, whereas line intensities especially from highly ionized species have a sensitivity of the timescale of ionization/recombination processes. Thus, spectroscopic observations of both continuum and line intensities have a capability of diagnostics of heating/cooling timescales. We perform a 1D hydrodynamic simulation coupled with the time-dependent ionization, and calculate continuum and line intensities under different heat input conditions in a coronal loop. We also examine the differential emission measure of the coronal loop from the time-integrated soft x-ray spectra. As a result, line intensity shows a departure from the ionization equilibrium and shows different responses depending on the frequency of the heat input. Solar soft X-ray spectroscopic imager will be mounted in the sounding rocket experiment of the Focusing Optics X-ray Solar Imager (FOXSI). This observation will deepen our understanding of heating processes to solve the “coronal heating problem”. Title: CLASP2: The Chromospheric LAyer Spectro-Polarimeter Authors: Rachmeler, Laurel; E McKenzie, David; Ishikawa, Ryohko; Trujillo Bueno, Javier; Auchère, Frédéric; Kobayashi, Ken; Winebarger, Amy; Bethge, Christian; Kano, Ryouhei; Kubo, Masahito; Song, Donguk; Narukage, Noriyuki; Ishikawa, Shin-nosuke; De Pontieu, Bart; Carlsson, Mats; Yoshida, Masaki; Belluzzi, Luca; Stepan, Jiri; del Pino Alemná, Tanausú; Ballester, Ernest Alsina; Asensio Ramos, Andres Bibcode: 2017SPD....4811010R Altcode: We present the instrument, science case, and timeline of the CLASP2 sounding rocket mission. The successful CLASP (Chromospheric Lyman-Alpha Spectro-Polarimeter) sounding rocket flight in 2015 resulted in the first-ever linear polarization measurements of solar hydrogen Lyman-alpha line, which is sensitive to the Hanle effect and can be used to constrain the magnetic field and geometric complexity of the upper chromosphere. Ly-alpha is one of several upper chromospheric lines that contain magnetic information. In the spring of 2019, we will re-fly the modified CLASP telescope to measure the full Stokes profile of Mg II h & k near 280 nm. This set of lines is sensitive to the upper chromospheric magnetic field via both the Hanle and the Zeeman effects. Title: CLASP2: The Chromospheric LAyer Spectro-Polarimeter Authors: Rachmeler, Laurel A.; McKenzie, D. E.; Ishikawa, R.; Trujillo-Bueno, J.; Auchere, F.; Kobayashi, K.; Winebarger, A.; Bethge, C.; Kano, R.; Kubo, M.; Song, D.; Narukage, N.; Ishikawa, S.; De Pontieu, B.; Carlsson, M.; Yoshida, M.; Belluzzi, L.; Stepan, J.; del Pino Alemán, T.; Alsina Ballester, E.; Asensio Ramos, A. Bibcode: 2017shin.confE..79R Altcode: We present the instrument, science case, and timeline of the CLASP2 sounding rocket mission. The successful CLASP (Chromospheric Lyman-Alpha Spectro-Polarimeter) sounding rocket flight in 2015 resulted in the first-ever linear polarization measurements of solar hydrogen Lyman-alpha line, which is sensitive to the Hanle effect and can be used to constrain the magnetic field and geometric complexity of the upper chromosphere. Ly-alpha is one of several upper chromospheric lines that contain magnetic information. In the spring of 2019, we will re-fly the modified CLASP telescope to measure the full Stokes profile of Mg II h & k near 280 nm. This set of lines is sensitive to the upper chromospheric magnetic field via both the Hanle and the Zeeman effects. Title: White paper of the "soft X-ray imaging spectroscopy" Authors: Narukage, Noriyuki; Ishikawa, Shin-nosuke; Kawate, Tomoko; Imada, Shinsuke; Sakao, Taro Bibcode: 2017arXiv170604536N Altcode: The solar corona is full of dynamic phenomena, e.g., solar flares, micro flares in active regions, jets in coronal holes and in the polar regions, X-ray bright points in quiet regions, etc. They are accompanied by interesting physical processes, namely, magnetic reconnection, particle acceleration, shocks, waves, flows, evaporation, heating, cooling, and so on. The understandings of these phenomena and processes have been progressing step-by-step with the evolution of the observation technology in EUV and X-rays from the space. But, there are fundamental questions remain unanswered, or haven't even addressed so far. Our scientific objective is to understand underlying physics of dynamic phenomena in the solar corona, covering some of the long-standing questions in solar physics such as particle acceleration in flares and coronal heating. In order to achieve these science objectives, we identify the imaging spectroscopy (the observations with spatial, temporal and energy resolutions) in the soft X-ray range (from ~0.5 keV to ~10 keV) is a powerful approach for the detection and analysis of energetic events. Title: Indication of the Hanle Effect by Comparing the Scattering Polarization Observed by CLASP in the Lyα and Si III 120.65 nm Lines Authors: Ishikawa, R.; Trujillo Bueno, J.; Uitenbroek, H.; Kubo, M.; Tsuneta, S.; Goto, M.; Kano, R.; Narukage, N.; Bando, T.; Katsukawa, Y.; Ishikawa, S.; Giono, G.; Suematsu, Y.; Hara, H.; Shimizu, T.; Sakao, T.; Winebarger, A.; Kobayashi, K.; Cirtain, J.; Champey, P.; Auchère, F.; Štěpán, J.; Belluzzi, L.; Asensio Ramos, A.; Manso Sainz, R.; De Pontieu, B.; Ichimoto, K.; Carlsson, M.; Casini, R. Bibcode: 2017ApJ...841...31I Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter is a sounding rocket experiment that has provided the first successful measurement of the linear polarization produced by scattering processes in the hydrogen Lyα line (121.57 nm) radiation of the solar disk. In this paper, we report that the Si III line at 120.65 nm also shows scattering polarization and we compare the scattering polarization signals observed in the Lyα and Si III lines in order to search for observational signatures of the Hanle effect. We focus on four selected bright structures and investigate how the U/I spatial variations vary between the Lyα wing, the Lyα core, and the Si III line as a function of the total unsigned photospheric magnetic flux estimated from Solar Dynamics Observatory/Helioseismic and Magnetic Imager observations. In an internetwork region, the Lyα core shows an antisymmetric spatial variation across the selected bright structure, but it does not show it in other more magnetized regions. In the Si III line, the spatial variation of U/I deviates from the above-mentioned antisymmetric shape as the total unsigned photospheric magnetic flux increases. A plausible explanation of this difference is the operation of the Hanle effect. We argue that diagnostic techniques based on the scattering polarization observed simultaneously in two spectral lines with very different sensitivities to the Hanle effect, like Lyα and Si III, are of great potential interest for exploring the magnetism of the upper solar chromosphere and transition region. Title: Polarization Calibration of the Chromospheric Lyman-Alpha SpectroPolarimeter for a 0.1% Polarization Sensitivity in the VUV Range. Part II: In-Flight Calibration Authors: Giono, G.; Ishikawa, R.; Narukage, N.; Kano, R.; Katsukawa, Y.; Kubo, M.; Ishikawa, S.; Bando, T.; Hara, H.; Suematsu, Y.; Winebarger, A.; Kobayashi, K.; Auchère, F.; Trujillo Bueno, J.; Tsuneta, S.; Shimizu, T.; Sakao, T.; Cirtain, J.; Champey, P.; Asensio Ramos, A.; Štěpán, J.; Belluzzi, L.; Manso Sainz, R.; De Pontieu, B.; Ichimoto, K.; Carlsson, M.; Casini, R.; Goto, M. Bibcode: 2017SoPh..292...57G Altcode: The Chromospheric Lyman-Alpha SpectroPolarimeter is a sounding rocket instrument designed to measure for the first time the linear polarization of the hydrogen Lyman-α line (121.6 nm). The instrument was successfully launched on 3 September 2015 and observations were conducted at the solar disc center and close to the limb during the five-minutes flight. In this article, the disc center observations are used to provide an in-flight calibration of the instrument spurious polarization. The derived in-flight spurious polarization is consistent with the spurious polarization levels determined during the pre-flight calibration and a statistical analysis of the polarization fluctuations from solar origin is conducted to ensure a 0.014% precision on the spurious polarization. The combination of the pre-flight and the in-flight polarization calibrations provides a complete picture of the instrument response matrix, and a proper error transfer method is used to confirm the achieved polarization accuracy. As a result, the unprecedented 0.1% polarization accuracy of the instrument in the vacuum ultraviolet is ensured by the polarization calibration. Title: Discovery of Scattering Polarization in the Hydrogen Lyα Line of the Solar Disk Radiation Authors: Kano, R.; Trujillo Bueno, J.; Winebarger, A.; Auchère, F.; Narukage, N.; Ishikawa, R.; Kobayashi, K.; Bando, T.; Katsukawa, Y.; Kubo, M.; Ishikawa, S.; Giono, G.; Hara, H.; Suematsu, Y.; Shimizu, T.; Sakao, T.; Tsuneta, S.; Ichimoto, K.; Goto, M.; Belluzzi, L.; Štěpán, J.; Asensio Ramos, A.; Manso Sainz, R.; Champey, P.; Cirtain, J.; De Pontieu, B.; Casini, R.; Carlsson, M. Bibcode: 2017ApJ...839L..10K Altcode: 2017arXiv170403228K There is a thin transition region (TR) in the solar atmosphere where the temperature rises from 10,000 K in the chromosphere to millions of degrees in the corona. Little is known about the mechanisms that dominate this enigmatic region other than the magnetic field plays a key role. The magnetism of the TR can only be detected by polarimetric measurements of a few ultraviolet (UV) spectral lines, the Lyα line of neutral hydrogen at 121.6 nm (the strongest line of the solar UV spectrum) being of particular interest given its sensitivity to the Hanle effect (the magnetic-field-induced modification of the scattering line polarization). We report the discovery of linear polarization produced by scattering processes in the Lyα line, obtained with the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) rocket experiment. The Stokes profiles observed by CLASP in quiet regions of the solar disk show that the Q/I and U/I linear polarization signals are of the order of 0.1% in the line core and up to a few percent in the nearby wings, and that both have conspicuous spatial variations with scales of ∼10 arcsec. These observations help constrain theoretical models of the chromosphere-corona TR and extrapolations of the magnetic field from photospheric magnetograms. In fact, the observed spatial variation from disk to limb of polarization at the line core and wings already challenge the predictions from three-dimensional magnetohydrodynamical models of the upper solar chromosphere. Title: High-Reflectivity Coatings for a Vacuum Ultraviolet Spectropolarimeter Authors: Narukage, Noriyuki; Kubo, Masahito; Ishikawa, Ryohko; Ishikawa, Shin-nosuke; Katsukawa, Yukio; Kobiki, Toshihiko; Giono, Gabriel; Kano, Ryouhei; Bando, Takamasa; Tsuneta, Saku; Auchère, Frédéric; Kobayashi, Ken; Winebarger, Amy; McCandless, Jim; Chen, Jianrong; Choi, Joanne Bibcode: 2017SoPh..292...40N Altcode: Precise polarization measurements in the vacuum ultraviolet (VUV) region are expected to be a new tool for inferring the magnetic fields in the upper atmosphere of the Sun. High-reflectivity coatings are key elements to achieving high-throughput optics for precise polarization measurements. We fabricated three types of high-reflectivity coatings for a solar spectropolarimeter in the hydrogen Lyman-α (Lyα ; 121.567 nm) region and evaluated their performance. The first high-reflectivity mirror coating offers a reflectivity of more than 80 % in Lyα optics. The second is a reflective narrow-band filter coating that has a peak reflectivity of 57 % in Lyα , whereas its reflectivity in the visible light range is lower than 1/10 of the peak reflectivity (∼5 % on average). This coating can be used to easily realize a visible light rejection system, which is indispensable for a solar telescope, while maintaining high throughput in the Lyα line. The third is a high-efficiency reflective polarizing coating that almost exclusively reflects an s-polarized beam at its Brewster angle of 68° with a reflectivity of 55 %. This coating achieves both high polarizing power and high throughput. These coatings contributed to the high-throughput solar VUV spectropolarimeter called the Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP), which was launched on 3 September, 2015. Title: Polarization Calibration of the Chromospheric Lyman-Alpha SpectroPolarimeter for a 0.1 % Polarization Sensitivity in the VUV Range. Part I: Pre-flight Calibration Authors: Giono, G.; Ishikawa, R.; Narukage, N.; Kano, R.; Katsukawa, Y.; Kubo, M.; Ishikawa, S.; Bando, T.; Hara, H.; Suematsu, Y.; Winebarger, A.; Kobayashi, K.; Auchère, F.; Trujillo Bueno, J. Bibcode: 2016SoPh..291.3831G Altcode: 2016SoPh..tmp..177G The Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) is a sounding rocket experiment designed to measure for the first time the linear polarization of the hydrogen Lyman-α line (121.6 nm) and requires a 0.1 % polarization sensitivity, which is unprecedented for a spectropolarimeter in the vacuum UV (VUV) spectral range. Title: Creation of Super-Hot Plasmas in a Flux Eruption Event as seen in Soft X-rays with Hinode/XRT Authors: Sakao, T.; Shimojo, M.; Narukage, N. Bibcode: 2016AGUFMSH11D..04S Altcode: The X-Ray Telescope (XRT) aboard Hinode observes soft X-ray emission from the solar corona with its energy range 0.06 - 2 keV and is capable of imaging, and diagnosing, a wide range of coronal temperatures from below 1 MK to beyond 20 MK, without gaps in the temperature coverage. In particular, the grazing-incidence nature of the XRT optics is suited for imaging high-temperature plasmas (>20 MK) created during the course of flares that are not necessarily well accessible with coronal imagers utilizing EUV emission lines. We report XRT observations of an eruptive flare (GOES M1.1) that took place behind the east limb at 18:30 UT on 14 October 2014. X-ray images traced a flux eruption which corresponds to the early stage of a CME observed with SoHO/LASCO, with a flux-rope-like feature ejected as the flare progressed. Filter-ratio temperatures of the soft X-ray flaring structure derived from multiple-filter observation of the flare suggest possible creation of super-hot (reaching as high as 30 MK) plasmas that distributed from near the apex of the erupting structure (where the flux rope was present), downwards along the sides of the structure. The observation may be the first identification in images of super-hot plasmas in the soft X-ray range, covering up to 2 keV. XRT observations on the creation of super-hot plasmas during the course of the flux eruption will be reported and its implication discussed. Title: Discovery of Ubiquitous Fast-Propagating Intensity Disturbances by the Chromospheric Lyman Alpha Spectropolarimeter (CLASP) Authors: Kubo, M.; Katsukawa, Y.; Suematsu, Y.; Kano, R.; Bando, T.; Narukage, N.; Ishikawa, R.; Hara, H.; Giono, G.; Tsuneta, S.; Ishikawa, S.; Shimizu, T.; Sakao, T.; Winebarger, A.; Kobayashi, K.; Cirtain, J.; Champey, P.; Auchère, F.; Trujillo Bueno, J.; Asensio Ramos, A.; Štěpán, J.; Belluzzi, L.; Manso Sainz, R.; De Pontieu, B.; Ichimoto, K.; Carlsson, M.; Casini, R.; Goto, M. Bibcode: 2016ApJ...832..141K Altcode: High-cadence observations by the slit-jaw (SJ) optics system of the sounding rocket experiment known as the Chromospheric Lyman Alpha Spectropolarimeter (CLASP) reveal ubiquitous intensity disturbances that recurrently propagate in either the chromosphere or the transition region or both at a speed much higher than the speed of sound. The CLASP/SJ instrument provides a time series of two-dimensional images taken with broadband filters centered on the Lyα line at a 0.6 s cadence. The multiple fast-propagating intensity disturbances appear in the quiet Sun and in an active region, and they are clearly detected in at least 20 areas in a field of view of 527″ × 527″ during the 5 minute observing time. The apparent speeds of the intensity disturbances range from 150 to 350 km s-1, and they are comparable to the local Alfvén speed in the transition region. The intensity disturbances tend to propagate along bright elongated structures away from areas with strong photospheric magnetic fields. This suggests that the observed fast-propagating intensity disturbances are related to the magnetic canopy structures. The maximum distance traveled by the intensity disturbances is about 10″, and the widths are a few arcseconds, which are almost determined by a pixel size of 1.″03. The timescale of each intensity pulse is shorter than 30 s. One possible explanation for the fast-propagating intensity disturbances observed by CLASP is magnetohydrodynamic fast-mode waves. Title: Quiet-sun and non-flaring active region measurements from the FOXSI-2 sounding rocket Authors: Buitrago-Casas, J. C.; Glesener, L.; Christe, S.; Ishikawa, S. N.; Narukage, N.; Krucker, S.; Bale, S. D. Bibcode: 2016AGUFMSH13A2280B Altcode: Solar hard X-ray (HXR) emissions are a cornerstone for understanding particle acceleration and energy release in the corona. These phenomena are present at different size scales and intensities, from large eruptive events down to the smallest flares. The presence of HXRs in small, unresolved flares would provide direct evidence of small reconnection events, i.e. nano-flares, that are thought to be be important for the unsolved coronal heating problem. Currently operating solar-dedicated instruments that observe HXRs from the Sun do not have the dynamic range, nor the sensitivity, crucial to observe the faintest solar HXRs. The Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket payload is a novel experiment that develops and applies direct focusing optics coupled with semiconductor detectors to observe faint HXRs from the Sun. The FOXSI rocket has successfully completed two flights, observing areas of the quiet-Sun, active regions and micro-flares. We present recent data analysis to test the presence of hot plasma in and outside of active regions observed during the two flights, focusing on the differential emission measure distribution of the non-flaring corona. Title: Optical alignment of the Chromospheric Lyman-Alpha Spectro-Polarimeter using sophisticated methods to minimize activities under vacuum Authors: Giono, G.; Katsukawa, Y.; Ishikawa, R.; Narukage, N.; Kano, R.; Kubo, M.; Ishikawa, S.; Bando, T.; Hara, H.; Suematsu, Y.; Winebarger, A.; Kobayashi, K.; Auchère, F.; Trujillo Bueno, J. Bibcode: 2016SPIE.9905E..3DG Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a sounding-rocket instrument developed at the National Astronomical Observatory of Japan (NAOJ) as a part of an international collaboration. The instrument main scientific goal is to achieve polarization measurement of the Lyman-α line at 121.56 nm emitted from the solar upper-chromosphere and transition region with an unprecedented 0.1% accuracy. The optics are composed of a Cassegrain telescope coated with a "cold mirror" coating optimized for UV reflection and a dual-channel spectrograph allowing for simultaneous observation of the two orthogonal states of polarization. Although the polarization sensitivity is the most important aspect of the instrument, the spatial and spectral resolutions of the instrument are also crucial to observe the chromospheric features and resolve the Ly-α profiles. A precise alignment of the optics is required to ensure the resolutions, but experiments under vacuum conditions are needed since Ly-α is absorbed by air, making the alignment experiments difficult. To bypass this issue, we developed methods to align the telescope and the spectrograph separately in visible light. We explain these methods and present the results for the optical alignment of the CLASP telescope and spectrograph. We then discuss the combined performances of both parts to derive the expected resolutions of the instrument, and compare them with the flight observations performed on September 3rd 2015. Title: Chromospheric LAyer SpectroPolarimeter (CLASP2) Authors: Narukage, Noriyuki; McKenzie, David E.; Ishikawa, Ryoko; Trujillo-Bueno, Javier; De Pontieu, Bart; Kubo, Masahito; Ishikawa, Shin-nosuke; Kano, Ryouhei; Suematsu, Yoshinori; Yoshida, Masaki; Rachmeler, Laurel A.; Kobayashi, Ken; Cirtain, Jonathan W.; Winebarger, Amy R.; Asensio Ramos, Andres; del Pino Aleman, Tanausu; Štępán, Jiri; Belluzzi, Luca; Larruquert, Juan Ignacio; Auchère, Frédéric; Leenaarts, Jorrit; Carlsson, Mattias J. L. Bibcode: 2016SPIE.9905E..08N Altcode: The sounding rocket Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) was launched on September 3rd, 2015, and successfully detected (with a polarization accuracy of 0.1 %) the linear polarization signals (Stokes Q and U) that scattering processes were predicted to produce in the hydrogen Lyman-alpha line (Lyα 121.567 nm). Via the Hanle effect, this unique data set may provide novel information about the magnetic structure and energetics in the upper solar chromosphere. The CLASP instrument was safely recovered without any damage and we have recently proposed to dedicate its second flight to observe the four Stokes profiles in the spectral region of the Mg II h and k lines around 280 nm; in these lines the polarization signals result from scattering processes and the Hanle and Zeeman effects. Here we describe the modifications needed to develop this new instrument called the "Chromospheric LAyer SpectroPolarimeter" (CLASP2). Title: Evidence of Electron Acceleration around the Reconnection X-point in a Solar Flare Authors: Narukage, Noriyuki; Shimojo, Masumi; Sakao, Taro Bibcode: 2016SPD....4730202N Altcode: Particle acceleration is one of the most significant features that are ubiquitous among space and cosmic plasmas. It is most prominent during flares in the case of the Sun, with which huge amounts of electromagnetic radiation and high-energy particles are expelled into the interplanetary space through acceleration of plasma particles in the corona. Though it has been well understood that energies of flares are supplied by the mechanism called magnetic reconnection based on the observations in X-rays and EUV with space telescopes, where and how in the flaring magnetic field plasmas are accelerated has remained unknown due to the low plasma density in the flaring corona. We here report the first observational identification of the energetic non-thermal electrons around the point of the ongoing magnetic reconnection (X-point), with the location of the X-point identified by soft X-ray imagery and the localized presence of non-thermal electrons identified from imaging-spectroscopic data at two microwave frequencies. Considering the existence of the reconnection outflows that carries both plasma particles and magnetic fields out from the X-point, our identified non-thermal microwave emissions around the X-point indicate that the electrons are accelerated around the reconnection X-point. Title: Spectro-polarimetric observation in UV with CLASP to probe the chromosphere and transition region Authors: Kano, Ryouhei; Ishikawa, Ryohko; Winebarger, Amy R.; Auchère, Frédéric; Trujillo Bueno, Javier; Narukage, Noriyuki; Kobayashi, Ken; Bando, Takamasa; Katsukawa, Yukio; Kubo, Masahito; Ishikawa, Shin-Nosuke; Giono, Gabriel; Hara, Hirohisa; Suematsu, Yoshinori; Shimizu, Toshifumi; Sakao, Taro; Tsuneta, Saku; Ichimoto, Kiyoshi; Goto, Motoshi; Cirtain, Jonathan W.; De Pontieu, Bart; Casini, Roberto; Manso Sainz, Rafael; Asensio Ramos, Andres; Stepan, Jiri; Belluzzi, Luca; Carlsson, Mats Bibcode: 2016SPD....4710107K Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a NASA sounding-rocket experiment that was performed in White Sands in the US on September 3, 2015. During its 5-minute ballistic flight, CLASP successfully made the first spectro-polarimetric observation in the Lyman-alpha line (121.57 nm) originating in the chromosphere and transition region. Since the Lyman-alpha polarization is sensitive to magnetic field of 10-100 G by the Hanle effect, we aim to infer the magnetic field information in such upper solar atmosphere with this experiment.The obtained CLASP data showed that the Lyman-alpha scattering polarization is about a few percent in the wings and the order of 0.1% in the core near the solar limb, as it had been theoretically predicted, and that both polarization signals have a conspicuous spatio-temporal variability. CLASP also observed another upper-chromospheric line, Si III (120.65 nm), whose critical field strength for the Hanle effect is 290 G, and showed a measurable scattering polarization of a few % in this line. The polarization properties of the Si III line could facilitate the interpretation of the scattering polarization observed in the Lyman-alpha line.In this presentation, we would like to show how the upper chromosphere and transition region are seen in the polarization of these UV lines and discuss the possible source of these complicated polarization signals. Title: Development of precision Wolter mirrors for future solar x-ray observations Authors: Sakao, Taro; Matsuyama, Satoshi; Kime, Ayumi; Goto, Takumi; Nishihara, Akihiko; Nakamori, Hiroki; Yamauchi, Kazuto; Kohmura, Yoshiki; Miyake, Akira; Hashizume, Hirokazu; Maezawa, Tadakazu; Suematsu, Yoshinori; Narukage, Noriyuki Bibcode: 2015SPIE.9603E..0US Altcode: High resolution imagery of the solar X-ray corona provides a crucial key to understand dynamics and heating processes of plasma particles there. However, X-ray imagery of the Sun with sub-arcsecond resolution has yet to be conducted due to severe technical difficulty in fabricating precision Wolter mirrors. For future X-ray observations of the Sun's corona, we are attempting to realize precision Wolter mirrors with sub-arcsecond resolution by adopting advanced surface polish and metrology methods based on nano-technology to sector mirrors which consist of a portion of an entire annulus. Following fabrication of the first engineering mirror and subsequent evaluation on the X-ray focusing performance in 2013, the second engineering mirror was made with improvements in both precision polish and metrology introduced. Measurement of focusing performance on the second mirror at SPring-8 synchrotron facility with 8 keV X-rays has demonstrated that the FWHM size of the PSF core reached down to 0.2" while its HPD (Half Power Diameter) size remained at ~3" due to the presence of small-angle scatter just outside of the core. Also, there was notable difference in the focal length between sagittal and meridional focusing which could have been caused by an error in the sag in the meridional direction of <10 nm in the mirror area. Further improvements to overcome these issues have been planned for the next engineering mirror. Title: CLASP: A UV Spectropolarimeter on a Sounding Rocket for Probing theChromosphere-Corona Transition Regio Authors: Ishikawa, Ryohko; Kano, Ryouhei; Winebarger, Amy; Auchere, Frederic; Trujillo Bueno, Javier; Bando, Takamasa; Narukage, Noriyuki; Kobayashi, Ken; Katsukawa, Yukio; Kubo, Masahito; Ishikawa, Shin-nosuke; Giono, Gabriel; Tsuneta, Saku; Hara, Hirohisa; Suematsu, Yoshinori; Shimizu, Toshifumi; Sakao, Taro; Ichimoto, Kiyoshi; Cirtain, Jonathan; De Pontieu, Bart; Casini, Roberto; Manso Sainz, Rafael; Asensio Ramos, Andres; Stepan, Jiri; Belluzzi, Luca Bibcode: 2015IAUGA..2254536I Altcode: The wish to understand the energetic phenomena of the outer solar atmosphere makes it increasingly important to achieve quantitative information on the magnetic field in the chromosphere-corona transition region. To this end, we need to measure and model the linear polarization produced by scattering processes and the Hanle effect in strong UV resonance lines, such as the hydrogen Lyman-alpha line. A team consisting of Japan, USA, Spain, France, and Norway has been developing a sounding rocket experiment called the Chromospheric Lyman-alpha Spectro-Polarimeter (CLASP). The aim is to detect the scattering polarization produced by anisotropic radiation pumping in the hydrogen Lyman-alpha line (121.6 nm), and via the Hanle effect to try to constrain the magnetic field vector in the upper chromosphere and transition region. In this talk, we will present an overview of our CLASP mission, its scientific objectives, ground tests made, and the latest information on the launch planned for the Summer of 2015. Title: Strategy for Realizing High-Precision VUV Spectro-Polarimeter Authors: Ishikawa, R.; Narukage, N.; Kubo, M.; Ishikawa, S.; Kano, R.; Tsuneta, S. Bibcode: 2014SoPh..289.4727I Altcode: 2014SoPh..tmp..116I Spectro-polarimetric observations in the vacuum ultraviolet (VUV) range are currently the only means to measure magnetic fields in the upper chromosphere and transition region of the solar atmosphere. The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) aims to measure linear polarization at the hydrogen Lyman-α line (121.6 nm). This measurement requires a polarization sensitivity better than 0.1 %, which is unprecedented in the VUV range. We here present a strategy with which to realize such high-precision spectro-polarimetry. This involves the optimization of instrument design, testing of optical components, extensive analyses of polarization errors, polarization calibration of the instrument, and calibration with onboard data. We expect that this strategy will aid the development of other advanced high-precision polarimeters in the UV as well as in other wavelength ranges. Title: Precision VUV Spectro-Polarimetry for Solar Chromospheric Magnetic Field Measurements Authors: Ishikawa, R.; Bando, T.; Hara, H.; Ishikawa, S.; Kano, R.; Kubo, M.; Katsukawa, Y.; Kobiki, T.; Narukage, N.; Suematsu, Y.; Tsuneta, S.; Aoki, K.; Miyagawa, K.; Ichimoto, K.; Kobayashi, K.; Auchère, F.; Clasp Team Bibcode: 2014ASPC..489..319I Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a VUV spectro-polarimeter optimized for measuring the linear polarization of the Lyman-α line (121.6 nm) to be launched in 2015 with NASA's sounding rocket (Ishikawa et al. 2011; Narukage et al. 2011; Kano et al. 2012; Kobayashi et al. 2012). With this experiment, we aim to (1) observe the scattering polarization in the Lyman-α line, (2) detect the Hanle effect, and (3) assess the magnetic fields in the upper chromosphere and transition region for the first time. The polarization measurement error consists of scale error δ a (error in amplitude of linear polarization), azimuth error Δφ (error in the direction of linear polarization), and spurious polarization ɛ (false linear polarization signals). The error ɛ should be suppressed below 0.1% in the Lyman-α core (121.567 nm ±0.02 nm), and 0.5% in the Lyman-α wing (121.567 nm ±0.05 nm), based on our scientific requirements shown in Table 2 of Kubo et al. (2014). From scientific justification, we adopt Δ φ<2° and δ a<10% as the instrument requirements. The spectro-polarimeter features a continuously rotating MgF2 waveplate (Ishikawa et al. 2013), a dual-beam spectrograph with a spherical grating working also as a beam splitter, and two polarization analyzers (Bridou et al. 2011), which are mounted at 90 degree from each other to measure two orthogonal polarization simultaneously. For the optical layout of the CLASP instrument, see Figure 3 in Kubo et al. (2014). Considering the continuous rotation of the half-waveplate, the modulation efficiency is 0.64 both for Stokes Q and U. All the raw data are returned and demodulation (successive addition or subtraction of images) is done on the ground.

We control the CLASP polarization performance in the following three steps. First, we evaluate the throughput and polarization properties of each optical component in the Lyman-α line, using the Ultraviolet Synchrotron ORbital Radiation Facility (UVSOR) at the Institute for Molecular Science. The second step is polarization calibration of the spectro-polarimeter after alignment. Since the spurious polarization caused by the axisymmetric telescope is estimated to be negligibly small because of the symmetry (Ishikawa et al. 2014), we do not perform end-to-end polarization calibration. As the final step, before the scientific observation near the limb, we make a short observation at the Sun center and verify the polarization sensitivity, because the scattering polarization is expected to be close to zero at the Sun center due to symmetric geometry. In order to clarify whether we will be able to achieve the required polarization sensitivity and accuracy via these steps, we exercise polarization error budget, by investigating all the possible causes and their magnitudes of polarization errors, all of which are not necessarily verified by the polarization calibration. Based on these error budgets, we conclude that a polarization sensitivity of 0.1% in the line core, δ a<10% and Δ φ<2° can be achieved combined with the polarization calibration of the spectro-polarimeter and the onboard calibration at the Sun center(refer to Ishikawa et al. 2014, for the detail).

We are currently conducting verification tests of the flight components and development of the UV light source for the polarization calibration. From 2014 spring, we will begin the integration, alignment, and calibration. We will update the error budgets throughout the course of these tests. Title: A Sounding Rocket Experiment for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) Authors: Kubo, M.; Kano, R.; Kobayashi, K.; Bando, T.; Narukage, N.; Ishikawa, R.; Tsuneta, S.; Katsukawa, Y.; Ishikawa, S.; Suematsu, Y.; Hara, H.; Shimizu, T.; Sakao, T.; Ichimoto, K.; Goto, M.; Holloway, T.; Winebarger, A.; Cirtain, J.; De Pontieu, B.; Casini, R.; Auchère, F.; Trujillo Bueno, J.; Manso Sainz, R.; Belluzzi, L.; Asensio Ramos, A.; Štěpán, J.; Carlsson, M. Bibcode: 2014ASPC..489..307K Altcode: A sounding-rocket experiment called the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is presently under development to measure the linear polarization profiles in the hydrogen Lyman-alpha (Lyα) line at 121.567 nm. CLASP is a vacuum-UV (VUV) spectropolarimeter to aim for first detection of the linear polarizations caused by scattering processes and the Hanle effect in the Lyα line with high accuracy (0.1%). This is a fist step for exploration of magnetic fields in the upper chromosphere and transition region of the Sun. Accurate measurements of the linear polarization signals caused by scattering processes and the Hanle effect in strong UV lines like Lyα are essential to explore with future solar telescopes the strength and structures of the magnetic field in the upper chromosphere and transition region of the Sun. The CLASP proposal has been accepted by NASA in 2012, and the flight is planned in 2015. Title: Current progress of optical alignment procedure of CLASP's Lyman-alpha polarimetry instrument Authors: Giono, G.; Ishikawa, R.; Katsukawa, Y.; Bando, T.; Kano, R.; Suematsu, Y.; Narukage, N.; Sakao, Taro; Kobayashi, K.; Auchère, F. Bibcode: 2014SPIE.9144E..3EG Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a sounding-rocket instrument currently under development at the National Astronomical Observatory of Japan (NAOJ) as a part of an international collaboration. CLASP's optics are composed of a Cassegrain telescope and a spectro-polarimeter which are designed to achieve an unprecedentedly accurate polarization measurement of the Ly-α line at 121.6nm emitted from the solar upper-chromosphere and transition region. CLASP's first flight is scheduled for August 2015. Reaching such accuracy requires a careful alignment of the optical elements to optimize the image quality at 121.6 nm. However Ly-α is absorbed by air and therefore the optics alignment has to be done under vacuum condition which makes any experiment difficult. To bypass this issue, we proposed to align the telescope and the spectrograph separately in visible light. Hence we present our alignment procedure for both telescope and spectro-polarimeter. We will explain details about the telescope preliminary alignment before mirrors coating, which was done in April 2014, present the telescope combined optical performance and compare them to CLASP tolerance. Then we will present details about an experiment designed to confirm our alignment procedure for the CLASP spectro-polarimeter. We will discuss the resulting image quality achieved during this experiment and the lessons learned. Title: The soft x-ray photon-counting telescope for solar observations Authors: Sakao, Taro; Narukage, Noriyuki; Suematsu, Yoshinori; Watanabe, Kyoko; Shimojo, Masumi; Imada, Shinsuke; Ishikawa, Shin-nosuke; DeLuca, Edward E. Bibcode: 2014SPIE.9144E..3DS Altcode: We present overview and development activities of a soft X-ray photon-counting spectroscopic imager for the solar corona that we conceive as a possible scientific payload for future space solar missions including Japanese Solar-C. The soft X-ray imager will employ a Wolter I grazing-incidence sector mirror with which images of the corona (1 MK to beyond 10 MK) will be taken with the highest-ever angular resolution (0.5"/pixel for a focal length of 4 m) as a solar Xray telescope. In addition to high-resolution imagery, we attempt to implement photon-counting capability for the imager by employing a backside-illuminated CMOS image sensor as the focal-plane device. Imaging-spectroscopy of the X-ray corona will be performed for the first time in the energy range from ~0.5 keV up to 10 keV. The imaging-spectroscopic observations with the soft X-ray imager will provide a noble probe for investigating mechanism(s) of magnetic reconnection and generation of supra-thermal (non-thermal) electrons associated with flares. Ongoing development activities in Japan towards the photon-counting imager is described with emphasis on that for sub-arcsecond-resolution grazing-incidence mirrors. Title: Evidence of Electron Acceleration around the Reconnection X-point in a Solar Flare Authors: Narukage, Noriyuki; Shimojo, Masumi; Sakao, Taro Bibcode: 2014ApJ...787..125N Altcode: 2014arXiv1404.3288N Particle acceleration is one of the most significant features that are ubiquitous among space and cosmic plasmas. It is most prominent during flares in the case of the Sun, with which huge amounts of electromagnetic radiation and high-energy particles are expelled into the interplanetary space through acceleration of plasma particles in the corona. Though it has been well understood that energies of flares are supplied by the mechanism called magnetic reconnection based on the observations in X-rays and EUV with space telescopes, where and how in the flaring magnetic field plasmas are accelerated has remained unknown due to the low plasma density in the flaring corona. We here report the first observational identification of the energetic non-thermal electrons around the point of the ongoing magnetic reconnection (X-point), with the location of the X-point identified by soft X-ray imagery and the localized presence of non-thermal electrons identified from imaging-spectroscopic data at two microwave frequencies. Considering the existence of the reconnection outflows that carries both plasma particles and magnetic fields out from the X-point, our identified non-thermal microwave emissions around the X-point indicate that the electrons are accelerated around the reconnection X-point. Additionally, the plasma around the X-point was also thermally heated up to 10 MK. The estimated reconnection rate of this event is ~0.017. Title: Coronal-Temperature-Diagnostic Capability of the Hinode/ X-Ray Telescope Based on Self-consistent Calibration. II. Calibration with On-Orbit Data Authors: Narukage, N.; Sakao, T.; Kano, R.; Shimojo, M.; Winebarger, A.; Weber, M.; Reeves, K. K. Bibcode: 2014SoPh..289.1029N Altcode: 2013arXiv1307.4489N The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager that observes the solar corona with the capability of diagnosing coronal temperatures from less than 1 MK to more than 10 MK. To make full use of this capability, Narukage et al. (Solar Phys.269, 169, 2011) determined the thickness of each of the X-ray focal-plane analysis filters based on calibration measurements from the ground-based end-to-end test. However, in their paper, the calibration of the thicker filters for observations of active regions and flares, namely the med-Be, med-Al, thick-Al and thick-Be filters, was insufficient due to the insufficient X-ray flux used in the measurements. In this work, we recalibrate those thicker filters using quiescent active region data taken with multiple filters of XRT. On the basis of our updated calibration results, we present the revised coronal-temperature-diagnostic capability of XRT. Title: Within the International Collaboration CHAIN: a Summary of Events Observed with Flare Monitoring Telescope (FMT) in Peru Authors: Ishitsuka, J.; Asai, A.; Morita, S.; Terrazas, R.; Cabezas, D.; Gutierrez, V.; Martinez, L.; Buleje, Y.; Loayza, R.; Nakamura, N.; Takasao, S.; Yoshinaga, Y.; Hillier, A.; Otsuji, K.; Shibata, K.; Ishitsuka, M.; Ueno, S.; Kitai, R.; Ishii, T.; Ichimoto, K.; Nagata, S.; Narukage, N. Bibcode: 2014SunGe...9...85I Altcode: In 2008 we inaugurated the new Solar Observatory in collaboration with Faculty of Sciences of San Luis Gonzaga de Ica National University, 300 km south of Lima. In March of 2010 a Flare Monitoring Telescope of Hida Observatory of Kyoto University arrived to Ica, part of CHAIN Project (Continuous H-alpha Imaging Network). In October of the same year we hosted the First FMT Workshop in Ica, then in July of 2011 the Second FMT Workshop was opened. Since that we are focused on two events registered by FMT in Peru to publish results. FMT is a good tool to introduce young people from universities into scientific knowledge; it is good also for education in Solar Physics and outreach. Details of this successful collaboration will be explained in this presentation. Title: Chromospheric Lyman-alpha spectro-polarimeter (CLASP) Authors: Kano, Ryouhei; Katsukawa, Yukio; Kubo, Masahito; Auchere, Frederic; Ishikawa, Ryohko; Kobayashi, Ken; Narukage, Noriyuki; Trujillo Bueno, Javier; Bando, Takamasa; Ishikawa, Shin-nosuke Bibcode: 2014cosp...40E1383K Altcode: In the solar chromosphere, magneto-hydrodynamic waves and super-sonic jets ubiquitously happen as revealed by the Japanese solar satellite Hinode. Now, we understand that the solar chromosphere is not a simple intermediate layer smoothly connecting the photosphere and corona, but a site where those dynamics may play an important role in the chromospheric and coronal heating. Such discoveries imply that the next frontier in solar physics lies in simultaneous observations between the dynamics and magnetic structures in the chromosphere and transition region, where the gas-dominant photosphere changes to the magnetic-dominant corona. Therefore, we promote the Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP), which is a NASA's sounding rocket experiment scheduled in 2015 for aiming to infer the magnetic field information in the solar chromosphere and transition region. CLASP makes precise measurement (0.1%) of the polarization profile of the Lyman-alpha line, and aims to make the first ever measurement of the Hanle effect polarization caused by magnetic fields in the upper solar atmosphere. It is also a pathfinder to establish a new measurement tool for chromospheric and transition-region magnetic fields, and to make progress on chromospheric studies in future missions. Title: UV spectropolarimeter design for precise polarization measurement and its application to the CLASP for exploration of magnetic fields in solar atmosphere Authors: Narukage, Noriyuki; Katsukawa, Yukio; Hara, Hirohisa; Kubo, Masahito; Auchere, Frederic; Ishikawa, Ryohko; Kano, Ryouhei; Bando, Takamasa; Ishikawa, Shin-nosuke; Suematsu, Yoshinori; Tsuneta, Saku Bibcode: 2014cosp...40E2232N Altcode: In order to measure the magnetic field in the region where the hot plasma from 10 (4) K to 10 (6) K is occupied, e.g., for solar atmosphere, the polarimetric measurements in ultra violet (UV) with 0.1% accuracy are required. In this paper, we propose a new UV spectropolarimeter design with 0.1% sensitivity in polarization measurement. This spectropolarimeter has two devices for the 0.1% accuracy. First, all optical components except the waveplate are the reflective type ones that can be equipped with the high reflectivity coating for the high throughput. Secondly, it equips the optically symmetric dual channels to measure the orthogonal linear polarization state simultaneously, using a concave diffraction grating as both the spectral dispersion element and the beam splitter. These two devices make the spurious polarizations caused by the photon noise, by the intensity variation of the observation target, and, by the instrument itself, enough small to achieve the 0.1% accuracy in polarization measurement. The spectropolarimeter thus designed is currently under fabrication for the sounding rocket project of Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) that aims at the direct measurement of the magnetic fields in solar atmosphere with Lyman-alpha line (121.6 nm) for the first time. Title: Chromospheric Lyman Alpha SpectroPolarimeter: CLASP Authors: Kobayashi, Ken; Kano, R.; Trujillo Bueno, J.; Winebarger, A. R.; Cirtain, J. W.; Bando, T.; De Pontieu, B.; Ishikawa, R.; Katsukawa, Y.; Kubo, M.; Narukage, N.; Sakao, T.; Tsuneta, S.; Auchère, F.; Asensio Ramos, A.; Belluzzi, L.; Carlsson, M.; Casini, R.; Hara, H.; Ichimoto, K.; Manso Sainz, R.; Shimizu, T.; Stepan, J.; Suematsu, Y.; Holloway, T. Bibcode: 2013SPD....44..142K Altcode: The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a VUV spectropolarimeter optimized for measuring the linear polarization of the Lyman-alpha line (121.6 nm). The Lyman-alpha line is predicted to show linear polarization caused by atomic scattering in the chromosphere and modified by the magnetic field through the Hanle effect. The Hanle effect is sensitive to weaker magnetic fields than Zeeman effect, and is not canceled by opposing fields, making it sensitive to tangled or unresolved magnetic field structures. These factors make the Hanle effect a valuable tool for probing the magnetic field in the chromosphere above the quiet sun. To meet this goal, CLASP is designed to measure linear polarization with 0.1% polarization sensitivity at 0.01 nm spectral resolution and 10" spatial resolution. CLASP is scheduled to be launched in 2015. Title: Temporal and Spatial Analyses of Spectral Indices of Nonthermal Emissions Derived from Hard X-Rays and Microwaves Authors: Asai, Ayumi; Kiyohara, Junko; Takasaki, Hiroyuki; Narukage, Noriyuki; Yokoyama, Takaaki; Masuda, Satoshi; Shimojo, Masumi; Nakajima, Hiroshi Bibcode: 2013ApJ...763...87A Altcode: 2012arXiv1212.1806A We studied electron spectral indices of nonthermal emissions seen in hard X-rays (HXRs) and microwaves. We analyzed 12 flares observed by the Hard X-Ray Telescope aboard Yohkoh, Nobeyama Radio Polarimeters, and the Nobeyama Radioheliograph (NoRH), and compared the spectral indices derived from total fluxes of HXRs and microwaves. Except for four events, which have very soft HXR spectra suffering from the thermal component, these flares show a gap Δδ between the electron spectral indices derived from HXRs δ X and those from microwaves δμ (Δδ = δ X - δμ) of about 1.6. Furthermore, from the start to the peak times of the HXR bursts, the time profiles of the HXR spectral index δ X evolve synchronously with those of the microwave spectral index δμ, keeping the constant gap. We also examined the spatially resolved distribution of the microwave spectral index by using NoRH data. The microwave spectral index δμ tends to be larger, which means a softer spectrum, at HXR footpoint sources with stronger magnetic field than that at the loop tops. These results suggest that the electron spectra are bent at around several hundreds of keV, and become harder at the higher energy range that contributes the microwave gyrosynchrotron emission. Title: Chromospheric Lyman-alpha spectro-polarimeter (CLASP) Authors: Kano, Ryouhei; Bando, Takamasa; Narukage, Noriyuki; Ishikawa, Ryoko; Tsuneta, Saku; Katsukawa, Yukio; Kubo, Masahito; Ishikawa, Shin-nosuke; Hara, Hirohisa; Shimizu, Toshifumi; Suematsu, Yoshinori; Ichimoto, Kiyoshi; Sakao, Taro; Goto, Motoshi; Kato, Yoshiaki; Imada, Shinsuke; Kobayashi, Ken; Holloway, Todd; Winebarger, Amy; Cirtain, Jonathan; De Pontieu, Bart; Casini, Roberto; Trujillo Bueno, Javier; Štepán, Jiří; Manso Sainz, Rafael; Belluzzi, Luca; Asensio Ramos, Andres; Auchère, Frédéric; Carlsson, Mats Bibcode: 2012SPIE.8443E..4FK Altcode: One of the biggest challenges in heliophysics is to decipher the magnetic structure of the solar chromosphere. The importance of measuring the chromospheric magnetic field is due to both the key role the chromosphere plays in energizing and structuring the outer solar atmosphere and the inability of extrapolation of photospheric fields to adequately describe this key boundary region. Over the last few years, significant progress has been made in the spectral line formation of UV lines as well as the MHD modeling of the solar atmosphere. It is found that the Hanle effect in the Lyman-alpha line (121.567 nm) is a most promising diagnostic tool for weaker magnetic fields in the chromosphere and transition region. Based on this groundbreaking research, we propose the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) to NASA as a sounding rocket experiment, for making the first measurement of the linear polarization produced by scattering processes and the Hanle effect in the Lyman-alpha line (121.567 nm), and making the first exploration of the magnetic field in the upper chromosphere and transition region of the Sun. The CLASP instrument consists of a Cassegrain telescope, a rotating 1/2-wave plate, a dual-beam spectrograph assembly with a grating working as a beam splitter, and an identical pair of reflective polarization analyzers each equipped with a CCD camera. We propose to launch CLASP in December 2014. Title: The x-ray/EUV telescope for the Solar-C mission: science and development activities Authors: Sakao, Taro; Narukage, Noriyuki; Imada, Shinsuke; Suematsu, Yoshinori; Shimojo, Masumi; Tsuneta, Saku; DeLuca, Edward E.; Watanabe, Kyoko; Ishikawa, Shin-nosuke Bibcode: 2012SPIE.8443E..0AS Altcode: We report science and development activities of the X-ray/EUV telescope for the Japanese Solar-C mission whose projected launch around 2019. The telescope consists of a package of (a) a normal-incidence (NI) EUV telescope and (b) a grazing-incidence (GI) soft X-ray telescope. The NI telescope chiefly provides images of low corona (whose temperature 1 MK or even lower) with ultra-high angular resolution (0.2-0.3"/pixel) in 3 wavelength bands (304, 171, and 94 angstroms). On the other hand, the GI telescope provides images of the corona with a wide temperature coverage (1 MK to beyond 10 MK) with the highest-ever angular resolution (~0.5"/pixel) as a soft X-ray coronal imager. The set of NI and GI telescopes should provide crucial information for establishing magnetic and gas-dynamic connection between the corona and the lower atmosphere of the Sun which is essential for understanding heating of, and plasma activities in, the corona. Moreover, we attempt to implement photon-counting capability for the GI telescope with which imaging-spectroscopy of the X-ray corona will be performed for the first time, in the energy range from ~0.5 keV up to 10 keV. The imaging-spectroscopic observations will provide totally-new information on mechanism(s) for the generation of hot coronal plasmas (heated beyond a few MK), those for magnetic reconnection, and even generation of supra-thermal electrons associated with flares. An overview of instrument outline and science for the X-ray photoncounting telescope are presented, together with ongoing development activities in Japan towards soft X-ray photoncounting observations, focusing on high-speed X-ray CMOS detector and sub-arcsecond-resolution GI mirror. Title: The Chromospheric Lyman-Alpha SpectroPolarimeter: CLASP Authors: Kobayashi, K.; Kano, R.; Trujillo-Bueno, J.; Asensio Ramos, A.; Bando, T.; Belluzzi, L.; Carlsson, M.; De Pontieu, R. C. B.; Hara, H.; Ichimoto, K.; Ishikawa, R.; Katsukawa, Y.; Kubo, M.; Manso Sainz, R.; Narukage, N.; Sakao, T.; Stepan, J.; Suematsu, Y.; Tsuneta, S.; Watanabe, H.; Winebarger, A. Bibcode: 2012ASPC..456..233K Altcode: The magnetic field plays a crucial role in the chromosphere and the transition region, and our poor empirical knowledge of the magnetic field in the upper chromosphere and transition region is a major impediment to advancing the understanding of the solar atmosphere. The Hanle effect promises to be a valuable alternative to Zeeman effect as a method of measuring the magnetic field in the chromosphere and transition region; it is sensitive to weaker magnetic fields, and also sensitive to tangled, unresolved field structures.

CLASP is a sounding rocket experiment that aims to observe the Hanle effect polarization of the Lyman α (1215.67Å) line in the solar chromosphere and transition region, and prove the usefulness of this technique in placing constraints on the magnetic field strength and orientation in the low plasma-β region of the solar atmosphere. The Ly-α line has been chosen because it is a chromospheric/transition-region line, and because the Hanle effect polarization of this line is predicted to be sensitive to 10-250 Gauss, encompassing the range of interest. The CLASP instrument is designed to measure linear polarization in the Ly-α line with a polarization sensitivity of 0.1%. The instrument is currently funded for development. The optical design of the instrument has been finalized, and an extensive series of component-level tests are underway to validate the design. Title: Ly-alpha polarimeter design for CLASP rocket experiment Authors: Kubo, M.; Watanabe, H.; Narukage, N.; Ishikawa, R.; Bando, T.; Kano, R.; Tsuneta, S.; Kobayashi, K.; Ichimoto, K.; Trujillo Bueno, J.; Song, D. Bibcode: 2011AGUFM.P11F1627K Altcode: A sounding-rocket program called the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is proposed to be launched in the Summer of 2014. CLASP will observe the upper solar chromosphere in Ly-alpha (121.567 nm), aiming to detect the linear polarization signal produced by scattering processes and the Hanle effect for the first time. The CLASP needs a rotating half-waveplate and a polarization analyzer working at the Ly-alpha wavelength to measure the linear polarization signal. We select Magnesium Fluoride (MgF2) as a material of the optical components because of its birefringent property and high transparency at UV wavelength. We have confirmed that the reflection at the Brewster's Angle of MgF2 plate is a good polarization analyzer for the Ly-alpha line by deriving its ordinary refractive index and extinction coefficient along the ordinary and extraordinary axes. These optical parameters are calculated with a least-square fitting in such a way that the reflectance and transmittance satisfy the Kramers-Kronig relation. The reflectance and transmittance against oblique incident angles for the s-polarized and the p-polarized light are measured using the synchrotron beamline at the Ultraviolet Synchrotron Orbital Radiation Facility (UVSOR). We have also measured a retardation of a zeroth-order waveplate made of MgF2. The thickness difference of the waveplate is 14.57 um.This waveplate works as a half-waveplate at 121.74 nm. From this measurement, we estimate that a waveplate with the thickness difference of 15.71 um will work as a half-waveplate at the Ly-alpha wavelength. We have developed a rotating waveplate - polarization analyzer system called a prototype of CLASP polarimeter, and input the perfect Stokes Q and U signals. The modulation patterns that are consistent with the theoretical prediction are successfully obtained in both cases. Title: The Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP)j Authors: Kobayashi, K.; Tsuneta, S.; Trujillo Bueno, J.; Bando, T.; Belluzzi, L.; Casini, R.; Carlsson, M.; Cirtain, J. W.; De Pontieu, B.; Hara, H.; Ichimoto, K.; Ishikawa, R.; Kano, R.; Katsukawa, Y.; Kim, T.; Kubo, M.; Manso Sainz, R.; Narukage, N.; Asensio Ramos, A.; Robinson, B.; Sakao, T.; Shimizu, T.; Stepan, J.; Suematsu, Y.; Watanabe, H.; West, E.; Winebarger, A. R. Bibcode: 2011AGUFM.P14C..05K Altcode: We present an overview of the Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) program. CLASP is a proposed sounding rocket experiment currently under development as collaboration between Japan, USA and Spain. The aim is to achieve the first measurement of magnetic field in the upper chromosphere and transition region of the Sun through the detection and measurement of Hanle effect polarization of the Lyman alpha line. The Hanle effect (i.e. the magnetic field induced modification of the linear polarization due to scattering processes in spectral lines) is believed to be a powerful tool for measuring the magnetic field in the upper chromosphere, as it is more sensitive to weaker magnetic fields than the Zeeman effect, and also sensitive to magnetic fields tangled at spatial scales too small to be resolved. The Lyman-alpha (121.567 nm) line has been chosen because it is a chromospheric/transition-region line, and because the Hanle effect polarization of the Lyman-alpha line is predicted to be sensitive to 10-250 Gauss, encompassing the range of interest. Hanle effect is predicted to be observable as linear polarization or depolarization, depending on the geometry, with a fractional polarization amplitude varying between 0.1% and 1% depending on the strength and orientation of the magnetic field. This quantification of the chromospheric magnetic field requires a highly sensitive polarization measurement. The CLASP instrument consists of a large aperture (287 mm) Cassegrain telescope mated to a polarizing beamsplitter and a matched pair of grating spectrographs. The polarizing beamsplitter consists of a continuously rotating waveplate and a linear beamsplitter, allowing simultaneous measurement of orthogonal polarizations and in-flight self-calibration. Development of the instrument is underway, and prototypes of all optical components have been tested using a synchrotron beamline. The experiment is proposed for flight in 2014. Title: Photon-counting soft x-ray telescope for the Solar-C mission Authors: Sakao, Taro; Narukage, Noriyuki; Shimojo, Masumi; Tsuneta, Saku; Suematsu, Yoshinori; Miyazaki, Satoshi; Imada, Shinsuke; Nishizuka, Naoto; Watanabe, Kyoko; Dotani, Tadayasu; DeLuca, Edward E.; Ishikawa, Shin-nosuke Bibcode: 2011SPIE.8148E..0CS Altcode: 2011SPIE.8148E..11S We report instrument outline as well as science of the photon-counting soft X-ray telescope that we have been studying as a possible scientific payload for the Japanese Solar-C mission whose projected launch around 2019. Soft X-rays (~1- 10 keV) from the solar corona include rich information on (1) possible mechanism(s) for heating the bright core of active regions seen in soft X-rays (namely, the hottest portion in the non-flaring corona), (2) dynamics and magnetohydrodynamic structures associated with magnetic reconnection processes ongoing in flares, and even (3) generation of supra-thermal distributions of coronal plasmas associated with flares. Nevertheless, imaging-spectroscopic investigation of the soft X-ray corona has so far remained unexplored due to difficulty in the instrumentation for achieving this aim. With the advent of recent remarkable progress in CMOS-APS detector technology, the photon-counting X-ray telescope will be capable of, in addition to conventional photon-integration type exposures, performing imaging-spectroscopic investigation on active regions and flares, thus providing, for example, detailed temperature information (beyond the sofar- utilized filter-ratio temperature) at each spatial point of the observing target. The photon-counting X-ray telescope will emply a Wolter type I optics with a piece of a segmented mirror whose focal length 4 meters, combined with a focal-plane CMOS-APS detector (0.4-0.5"/pixel) whose frame read-out rate required to be as high as 1000 fps. Title: Ly-alpha polarimeter design for CLASP rocket experiment Authors: Watanabe, H.; Narukage, N.; Kubo, M.; Ishikawa, R.; Bando, T.; Kano, R.; Tsuneta, S.; Kobayashi, K.; Ichimoto, K.; Trujillo-Bueno, J. Bibcode: 2011SPIE.8148E..0TW Altcode: 2011SPIE.8148E..25W; 2014arXiv1407.4577W A sounding-rocket program called the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is proposed to be launched in the summer of 2014. CLASP will observe the solar chromosphere in Ly-alpha (121.567 nm), aiming to detect the linear polarization signal produced by scattering processes and the Hanle effect for the first time. The polarimeter of CLASP consists of a rotating half-waveplate, a beam splitter, and a polarization analyzer. Magnesium Fluoride (MgF2) is used for these optical components, because MgF2 exhibits birefringent property and high transparency at ultraviolet wavelength. The development and comprehensive testing program of the optical components of the polarimeter is underway using the synchrotron beamline at the Ultraviolet Synchrotron Orbital Radiation Facility (UVSOR). The first objective is deriving the optical constants of MgF2 by the measurement of the reflectance and transmittance against oblique incident angles for the s-polarized and the p-polarized light. The ordinary refractive index and extinction coefficient along the ordinary and extraordinary axes are derived with a least-square fitting in such a way that the reflectance and transmittance satisfy the Kramers-Krönig relation. The reflection at the Brewster's Angle of MgF2 plate is confirmed to become a good polarization analyzer at Ly-alpha. The second objective is the retardation measurement of a zeroth-order waveplate made of MgF2. The retardation of a waveplate is determined by observing the modulation amplitude that comes out of a waveplate and a polarization analyzer. We tested a waveplate with the thickness difference of 14.57 um. The 14.57 um waveplate worked as a half-waveplate at 121.74 nm. We derived that a waveplate with the thickness difference of 15.71 um will work as a half-waveplate at Ly-alpha wavelength. We developed a prototype of CLASP polarimeter using the MgF2 half-waveplate and polarization analyzers, and succeeded in obtaining the modulation patterns that are consistent with the theoretical prediction. We confirm that the performance of the prototype is optimized for measuring linear polarization signal with the least effect of the crosstalk from the circular polarization. Title: Overview of Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) Authors: Narukage, Noriyuki; Tsuneta, Saku; Bando, Takamasa; Kano, Ryouhei; Kubo, Masahito; Ishikawa, Ryoko; Hara, Hirohisa; Suematsu, Yoshinori; Katsukawa, Yukio; Watanabe, Hiroko; Ichimoto, Kiyoshi; Sakao, Taro; Shimizu, Toshifumi; Kobayashi, Ken; Robinson, Brian; Kim, Tony; Winebarger, Amy; West, Edward; Cirtain, Jonathan; De Pontieu, Bart; Casini, Roberto; Trujillo Bueno, Javier; Stepan, Jiri; Manso Sainz, Rafael; Belluzzi, Luca; Asensio Ramos, Andres; Carlsson, Mats Bibcode: 2011SPIE.8148E..0HN Altcode: 2011SPIE.8148E..16N The solar chromosphere is an important boundary, through which all of the plasma, magnetic fields and energy in the corona and solar wind are supplied. Since the Zeeman splitting is typically smaller than the Doppler line broadening in the chromosphere and transition region, it is not effective to explore weak magnetic fields. However, this is not the case for the Hanle effect, when we have an instrument with high polarization sensitivity (~ 0.1%). "Chromospheric Lyman- Alpha SpectroPolarimeter (CLASP)" is the sounding rocket experiment to detect linear polarization produced by the Hanle effect in Lyman-alpha line (121.567 nm) and to make the first direct measurement of magnetic fields in the upper chromosphere and lower transition region. To achieve the high sensitivity of ~ 0.1% within a rocket flight (5 minutes) in Lyman-alpha line, which is easily absorbed by materials, we design the optical system mainly with reflections. The CLASP consists of a classical Cassegrain telescope, a polarimeter and a spectrometer. The polarimeter consists of a rotating 1/2-wave plate and two reflecting polarization analyzers. One of the analyzer also works as a polarization beam splitter to give us two orthogonal linear polarizations simultaneously. The CLASP is planned to be launched in 2014 summer. Title: Propagation of Moreton Waves Authors: Zhang, Yuzong; Kitai, Reizaburo; Narukage, Noriyuki; Matsumoto, Takuma; Ueno, Satoru; Shibata, Kazunari; Wang, Jingxiu Bibcode: 2011PASJ...63..685Z Altcode: With the Flare-Monitoring Telescope (FMT) and Solar Magnetic Activity Research Telescope (SMART) at Hida observatory of Kyoto University, 13 events of Moreton waves were captured at Hα center, Hα ±0.5 Å, and Hα ±0.8 Å wavebands since 1997. With such samples, we have studied the statistical properties of the propagation of Moreton waves. Moreton waves were all restricted in sectorial zones with a mean value of 92°. However, their accompanying EIT waves, observed simultaneously with SOHO/EIT at extreme-ultraviolet wavelength, were very isotropic with a quite extended scope of 193°. The average propagation speeds of the Moreton waves and the corresponding EIT waves were 664 km s-1 and 205 km s-1, respectively. Moreton waves propagated either under large-scale close magnetic flux loops, or firstly in the sectorial region where two sets of magnetic loops separated from each other and diverged, and then stopped before the open magnetic flux region. The location swept by Moreton waves had a relatively weak magnetic field as compared to the magnetic fields at their sidewalls. The ratio of the magnetic flux density between the sidewall and the path falls in the range of 1.4 to 3.7 at a height of 0.01 solar radii. Additionally, we roughly estimated the distribution of the fast magnetosonic speed between the propagating path and sidewalls in an event on 1997 November 3, and found a relatively low-fast magnetosonic speed in the path. We also found that the propagating direction of Moreton waves coincided with the direction of filament eruption in a few well-observed events. This favors an interpretation of the ``Piston'' model, although further studies are necessary for any definitive conclusion. Title: Imaging Observations of Coronal Magnetic Field by Nobeyama Radioheliograph Authors: Shibasaki, K.; Narukage, N.; Yoshimura, K. Bibcode: 2011ASPC..437..433S Altcode: Coronal magnetic field in a post flare arcade of loops above the solar limb is mapped by the Nobeyama Radioheliograph. Post flare loops are filled with hot and dense plasma threaded by magnetic field. Thermal free-free microwave emission from these plasma is bright enough to carefully measure circular polarization degree. As circular polarization is the result of gyration of electrons around magnetic field, inversion of circular polarization degree to magnetic field strength is simple. We successfully measured the circular polarization degree distribution at 17 GHz and got a magnetic field map in a post flare arcade of loops above the solar limb. Title: A Sounding Rocket Experiment for Spectropolarimetric Observations with the Lyα Line at 121.6 nm (CLASP) Authors: Ishikawa, R.; Bando, T.; Fujimura, D.; Hara, H.; Kano, R.; Kobiki, T.; Narukage, N.; Tsuneta, S.; Ueda, K.; Wantanabe, H.; Kobayashi, K.; Trujillo Bueno, J.; Manso Sainz, R.; Stepan, J.; de Pontieu, B.; Carlsson, M.; Casini, R. Bibcode: 2011ASPC..437..287I Altcode: A team consisting of Japan, USA, Spain, and Norway is developing a high-throughput Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP), which is proposed to fly with a NASA sounding rocket in 2014. CLASP will explore the magnetism of the upper solar chromosphere and transition region via the Hanle effect of the Lyα line for the first time. This experiment requires spectropolarimetric observations with high polarimetric sensitivity (∼0.1%) and wavelength resolution (0.1 Å). The final spatial resolution (slit width) is being discussed taking into account the required high signal-to-noise ratio. We have demonstrated the performance of the Lyα polarimeter by extensively using the Ultraviolet Synchrotron ORbital Radiation Facility (UVSOR) at the Institute for Molecular Sciences. In this contribution, we report these measurements at UVSOR together with the current status of the CLASP project. Title: Coronal-Temperature-Diagnostic Capability of the Hinode/ X-Ray Telescope Based on Self-Consistent Calibration Authors: Narukage, N.; Sakao, T.; Kano, R.; Hara, H.; Shimojo, M.; Bando, T.; Urayama, F.; DeLuca, E.; Golub, L.; Weber, M.; Grigis, P.; Cirtain, J.; Tsuneta, S. Bibcode: 2011SoPh..269..169N Altcode: 2010arXiv1011.2867N; 2011SoPh..tmp....1N The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager that observes the solar corona with unprecedentedly high angular resolution (consistent with its 1″ pixel size). XRT has nine X-ray analysis filters with different temperature responses. One of the most significant scientific features of this telescope is its capability of diagnosing coronal temperatures from less than 1 MK to more than 10 MK, which has never been accomplished before. To make full use of this capability, accurate calibration of the coronal temperature response of XRT is indispensable and is presented in this article. The effect of on-orbit contamination is also taken into account in the calibration. On the basis of our calibration results, we review the coronal-temperature-diagnostic capability of XRT. Title: A New View of the Sun with Hinode Mission Authors: Sakao, Taro; Tsuneta, Saku; Shimojo, Masumi; Narukage, Noriyuki; Kano, Ryouhei; Obara, Takahiro; Watari, Shinichi; Hinode Team Bibcode: 2009TrSpT...7Tr215S Altcode: We present highlights of observations of the Sun with Japanese Hinode mission launched by JAXA in September 2006. The scientific objective of Hinode mission is to observe, in an unprecedented detail, a wide variety of plasma activities in the Sun's corona together with magnetic activities on the photosphere and in the chromosphere, utilizing a suite of three state-of-the-art telescopes; Solar Optical Telescope (SOT), X-Ray Telescope (XRT), and EUV Imaging Spectrometer (EIS). Since the beginning of the observations late in October 2006, Hinode has been providing ample information on activities of magnetized plasmas in the solar atmosphere some of which are totally new to us. In this article, we present an overview of the Hinode mission as well as some highlights of the observations. Title: Plasma Outflows in the Corona as Observed With Hinode XRT Authors: Sakao, T.; Kano, R.; Narukage, N.; Deluca, E. E.; Grigis, P. Bibcode: 2008AGUFMSH41B1624S Altcode: We present imaging observations of plasma outflows in the solar corona made with X-Ray Telescope (XRT) aboard Hinode satellite. The XRT employs a back-illuminated CCD as the focal-plane imaging device which enables us, together with an optimized set of analysis filters, to investigate, for the first time, dynamic behavior of relatively cool (1-2 MK, say) plasmas in the corona. The XRT revealed a clear pattern of continuous outflow of plasmas from the edge of an active region NOAA AR 10942 right adjacent to a coronal hole. Plasmas of temperature ~1 MK flowed out with a sub-sonic velocity of typically ~140 km/s along magnetic field lines that are most likely open towards the interplanetary space. These outflowing plasmas may constitute a fraction of the (slow) solar wind. In addition to this discovery, the XRT has so far identified rich patterns of continuous outflows including those from coronal hole boundaries and along fan-like field lines rooted inside coronal holes. XRT observations of such plasma outflows in the corona are presented and their possible implications to the solar wind discussed. Title: The Thermal Structures of Solar Corona Revealed with Hinode/XRT Authors: Narukage, N.; Sakao, T.; Kano, R. Bibcode: 2008AGUFMSH52A..03N Altcode: The solar corona has a wide temperature range from less than 1MK (1,000,000K) to more than 10MK. The X-ray telescope (XRT) on board the Hinode satellite has 9 X-ray analysis filters with different temperature responses making it possible to detect both cool and hot coronal plasmas. Using the data observed with this telescope, we successfully derived the coronal temperature and emission measure around the whole sun, i.e., for not only active regions but also quiet regions and coronal holes. We also found that coronal structures are nicely classified using the temperature and emission measure. And the coronal structures were found to depend on the length of structure and the heating flux. Furthermore, we calculated the coronal potential magnetic field using the photospheric magnetic field. To compare the heating flux estimated with coronal temperature and the calculated coronal magnetic field might be the great clue to solving the big coronal heating question: why does the hot 1MK corona stably exist above the cool 6,000K solar surface? In this talk, we will show some results of our latest studies about the coronal thermal structures. Title: Observations and analysis of the April 9, 2008 CME using STEREO, Hinode TRACE and SoHO data Authors: Reeves, K. K.; Patsourakos, S.; Stenborg, G.; Miralles, M.; Deluca, E.; Forbes, T.; Golub, L.; Kasper, J.; Landi, E.; McKenzie, D.; Narukage, N.; Raymond, J.; Savage, S.; Su, Y.; van Ballegooijen, A.; Vourlidas, A.; Webb, D. Bibcode: 2008AGUFMSH12A..04R Altcode: On April 9, 2008 a CME originating from an active region behind the limb was well-observed by STEREO, Hinode, TRACE and SoHO. Several interesting features connected to this eruption were observed. (1) The interaction of the CME with open field lines from a nearby coronal hole appeared to cause an abrupt change in the direction of the CME ejecta. (2) The prominence material was heated, as evidenced by a change from absorption to emission in the EUV wavelengths. (3) Because the active region was behind the limb, the X-Ray Telescope on Hinode was able to take long enough exposure times to observe a faint current- sheet like structure, and it was able to monitor the dynamics of the plasma surrounding this structure. This event is also being studied in the context of activity that occurred during the Whole Heliosphere Interval (WHI). Title: Strongly Blueshifted Phenomena Observed with Hinode EIS in the 2006 December 13 Solar Flare Authors: Asai, Ayumi; Hara, Hirohisa; Watanabe, Tetsuya; Imada, Shinsuke; Sakao, Taro; Narukage, Noriyuki; Culhane, J. L.; Doschek, G. A. Bibcode: 2008ApJ...685..622A Altcode: 2008arXiv0805.4468A We present a detailed examination of strongly blueshifted emission lines observed with the EUV Imaging Spectrometer on board the Hinode satellite. We found two kinds of blueshifted phenomenon associated with the X3.4 flare that occurred on 2006 December 13. One was related to a plasmoid ejection seen in soft X-rays. It was very bright in all the lines used for the observations. The other was associated with the faint arc-shaped ejection seen in soft X-rays. The soft X-ray ejection is thought to be a magnetohydrodynamic (MHD) fast-mode shock wave. This is therefore the first spectroscopic observation of an MHD fast-mode shock wave associated with a flare. Title: Three Successive and Interacting Shock Waves Generated by a Solar Flare Authors: Narukage, Noriyuki; Ishii, Takako T.; Nagata, Shin'ichi; UeNo, Satoru; Kitai, Reizaburo; Kurokawa, Hiroki; Akioka, Maki; Shibata, Kazunari Bibcode: 2008ApJ...684L..45N Altcode: We discovered three successive Moreton waves generated by a single solar flare on 2005 August 3. Although this flare was not special in magnitude or configuration, Moreton waves (shock waves) successively occurred three times. Multiple shock waves generated during a single flare have not been reported before. Furthermore, the faster second-generated Moreton wave caught up and merged with the slower first-generated one. This is the first report of shock-shock interaction associated with a solar flare. The shock-plasma interaction was also detected. When the third-generated Moreton wave passed through an erupting filament, the filament was accelerated by the Moreton wave. In this event, filaments also erupted three times. On the basis of this observation, we consider that filament eruption is indispensable to the generation of Moreton waves. Title: Hinode/XRT Diagnostics of Loop Thermal Structure Authors: Reale, F.; Parenti, S.; Reeves, K. K.; Weber, M.; Bobra, M. G.; Barbera, M.; Kano, R.; Narukage, N.; Shimojo, M.; Sakao, T.; Peres, G.; Golub, L. Bibcode: 2008ASPC..397...50R Altcode: We investigate possible diagnostics of the thermal structure of coronal loops from Hinode/XRT observations made with several filters. We consider the observation of an active region with five filters. We study various possible combinations of filter data to optimize for sensitivity to thermal structure and for signal enhancement. Title: Vertical Temperature Structures of the Solar Corona Derived with the Hinode X-Ray Telescope Authors: Kano, Ryouhei; Sakao, Taro; Narukage, Noriyuki; Tsuneta, Saku; Kotoku, Jun'ichi; Bando, Takamasa; Deluca, Edward; Lundquist, Loraine; Golub, Leon; Hara, Hirohisa; Matsuzaki, Keiichi; Shimojo, Masumi; Shibasaki, Kiyoto; Shimizu, Toshifumi; Nakatani, Ichiro Bibcode: 2008PASJ...60..827K Altcode: We obtained temperature structures in faint coronal features above and near the solar limb with the X-Ray Telescope aboard the Hinode satellite by accurately correcting the scattered X-rays from surrounding bright regions with occulted images during the solar eclipses. Our analysis yields a polar coronal hole temperature of about 1.0MK and an emission measure in the range of 1025.5-1026.0cm-5. In addition, our methods allow us to measure the temperature and emission measure of two distinct quiet-Sun structures: radial (plume-like) structures near the boundary of the coronal-hole and diffuse quiet Sun regions at mid-latitudes. The radial structures appear to have increasing temperature with height during the first 100Mm, and constant temperatures above 100Mm. For the diffuse quiet-Sun region the temperatures are the highest just above the limb, and appear to decrease with height. These differences may be due to different magnetic configurations. Title: Molecular Contamination Assessments on <i>Hinode</i> X-Ray Telescope Authors: Urayama, Fumitaka; Bando, Takamasa; Kano, Ryouhei; Hara, Hirohisa; Narukage, Noriyuki; Sakao, Taro Bibcode: 2008JSASS..56..536U Altcode: The <i>Hinode</i> (Solar-B) was launched by M-V rocket on 22 September 2006 UT. The telemetry data of the <i>Hinode</i> X-ray Telescope (XRT) showed that the X-ray count rate detected with the XRT had decreased rapidly since the operational heaters on the XRT telescope tube were turned on. This is attributed to the fact that molecular contaminants accumulated onto the CCD with the temperature of -60ºC resulting in the degradation of the XRT sensitivity. We baked the CCD at the temperature of 35ºC in order to remove the contaminants from the CCD surface. However many contaminant spots appeared on the surface. We found that major contaminant source existed in the telescope tube, and identified the contaminants as diethylhexyl phthalate (DEHP) or DEHP-like organics. The mechanisms to yield the contaminant spots were discussed. Title: Relation between coronal temperature and magnetic field Authors: Narukage, Noriyuki; Kano, Ryouhei; Shiota, Daiko; Sakao, Taro Bibcode: 2008cosp...37.2184N Altcode: 2008cosp.meet.2184N The solar corona has a wide temperature range from less than 1MK to more than 10MK. The X-ray telescope (XRT) on board Hinode satellite has 9 X-ray analysis filters to observe the almost of whole coronal plasma. Using the data observed with this telescope, we successfully derived the coronal temperature around the whole sun. We found that coronal structures are nicely classified using the temperature and emission measure. The coronal structures were found to depend on the length of structure and the heating flux. Furthermore, we calculated the coronal potential magnetic field in high spatial resolution using the photospheric magnetic field observed with SOHO/MDI. To compare the heating flux estimated with coronal temperature and the calculated coronal magnetic field might be the great clue to solving the big coronal heating question. Title: Cross calibration of soft X-ray telescopes between Hinode/XRT and GOES13/SXI Authors: Narukage, N.; Sakao, T.; Kano, R.; Shimojo, M.; Cirtain, J.; Deluca, E.; Nitta, N.; Lemen, J. Bibcode: 2007AGUFMSH53A1050N Altcode: The X-Ray Telescope (XRT) aboard Hinode satellite is a grazing incidence telescope to observe all the coronal features with a wide temperature range from less than 1MK to more than 10MK. And the XRT has 9 X-ray analysis filters which are optimized to observed the almost whole coronal plasma and to derived the coronal temperature distribution. Meanwhile, the GOES13 satellite carries a Solar X-ray Imager (SXI) to monitor the solar X-rays. The SXI is also a grazing incidence telescope and has 7 X-ray filters. The XRT and SXI are similar telescopes to observe the dynamic solar corona. On 24 Nov 2006, the XRT and SXI-team performed the simultaneous observation for the cross calibration between XRT and SXI. In this study, we analyzed this data set and checked the actual characteristics of each X-ray analysis filter. Title: Slipping Magnetic Reconnection in Coronal Loops Authors: Aulanier, Guillaume; Golub, Leon; DeLuca, Edward E.; Cirtain, Jonathan W.; Kano, Ryouhei; Lundquist, Loraine L.; Narukage, Noriyuki; Sakao, Taro; Weber, Mark A. Bibcode: 2007Sci...318.1588A Altcode: Magnetic reconnection of solar coronal loops is the main process that causes solar flares and possibly coronal heating. In the standard model, magnetic field lines break and reconnect instantaneously at places where the field mapping is discontinuous. However, another mode may operate where the magnetic field mapping is continuous but shows steep gradients: The field lines may slip across each other. Soft x-ray observations of fast bidirectional motions of coronal loops, observed by the Hinode spacecraft, support the existence of this slipping magnetic reconnection regime in the Sun’s corona. This basic process should be considered when interpreting reconnection, both on the Sun and in laboratory-based plasma experiments. Title: Evidence for Alfvén Waves in Solar X-ray Jets Authors: Cirtain, J. W.; Golub, L.; Lundquist, L.; van Ballegooijen, A.; Savcheva, A.; Shimojo, M.; DeLuca, E.; Tsuneta, S.; Sakao, T.; Reeves, K.; Weber, M.; Kano, R.; Narukage, N.; Shibasaki, K. Bibcode: 2007Sci...318.1580C Altcode: Coronal magnetic fields are dynamic, and field lines may misalign, reassemble, and release energy by means of magnetic reconnection. Giant releases may generate solar flares and coronal mass ejections and, on a smaller scale, produce x-ray jets. Hinode observations of polar coronal holes reveal that x-ray jets have two distinct velocities: one near the Alfvén speed (~800 kilometers per second) and another near the sound speed (200 kilometers per second). Many more jets were seen than have been reported previously; we detected an average of 10 events per hour up to these speeds, whereas previous observations documented only a handful per day with lower average speeds of 200 kilometers per second. The x-ray jets are about 2 × 103 to 2 × 104 kilometers wide and 1 × 105 kilometers long and last from 100 to 2500 seconds. The large number of events, coupled with the high velocities of the apparent outflows, indicates that the jets may contribute to the high-speed solar wind. Title: Continuous Plasma Outflows from the Edge of a Solar Active Region as a Possible Source of Solar Wind Authors: Sakao, Taro; Kano, Ryouhei; Narukage, Noriyuki; Kotoku, Jun'ichi; Bando, Takamasa; DeLuca, Edward E.; Lundquist, Loraine L.; Tsuneta, Saku; Harra, Louise K.; Katsukawa, Yukio; Kubo, Masahito; Hara, Hirohisa; Matsuzaki, Keiichi; Shimojo, Masumi; Bookbinder, Jay A.; Golub, Leon; Korreck, Kelly E.; Su, Yingna; Shibasaki, Kiyoto; Shimizu, Toshifumi; Nakatani, Ichiro Bibcode: 2007Sci...318.1585S Altcode: The Sun continuously expels a huge amount of ionized material into interplanetary space as the solar wind. Despite its influence on the heliospheric environment, the origin of the solar wind has yet to be well identified. In this paper, we report Hinode X-ray Telescope observations of a solar active region. At the edge of the active region, located adjacent to a coronal hole, a pattern of continuous outflow of soft-x-ray emitting plasmas was identified emanating along apparently open magnetic field lines and into the upper corona. Estimates of temperature and density for the outflowing plasmas suggest a mass loss rate that amounts to ~1/4 of the total mass loss rate of the solar wind. These outflows may be indicative of one of the solar wind sources at the Sun. Title: Fine Thermal Structure of a Coronal Active Region Authors: Reale, Fabio; Parenti, Susanna; Reeves, Kathy K.; Weber, Mark; Bobra, Monica G.; Barbera, Marco; Kano, Ryouhei; Narukage, Noriyuki; Shimojo, Masumi; Sakao, Taro; Peres, Giovanni; Golub, Leon Bibcode: 2007Sci...318.1582R Altcode: The determination of the fine thermal structure of the solar corona is fundamental to constraining the coronal heating mechanisms. The Hinode X-ray Telescope collected images of the solar corona in different passbands, thus providing temperature diagnostics through energy ratios. By combining different filters to optimize the signal-to-noise ratio, we observed a coronal active region in five filters, revealing a highly thermally structured corona: very fine structures in the core of the region and on a larger scale further away. We observed continuous thermal distribution along the coronal loops, as well as entangled structures, and variations of thermal structuring along the line of sight. Title: A Study of Polar Jet Parameters Based on Hinode XRT Observations Authors: Savcheva, Antonia; Cirtain, Jonathan; Deluca, Edward E.; Lundquist, Loraine L.; Golub, Leon; Weber, Mark; Shimojo, Masumi; Shibasaki, Kiyoto; Sakao, Taro; Narukage, Noriyuki; Tsuneta, Saku; Kano, Ryouhei Bibcode: 2007PASJ...59S.771S Altcode: Hinode/SOHO campaign 7197 is the most extensive study of polar jet formation and evolution from within both the north and south polar coronal holes so far. For the first time, this study showed that the appearance of X-ray jets in the solar coronal holes occurs at very high frequency - about 60 jets d-1 on average. Using observations collected by the X-Ray Telescope on Hinode, a number of physical parameters from a large sample of jets were statistically studied. We measured the apparent outward velocity, the height, the width and the lifetime of the jets. In our sample, all of these parameters show peaked distributions with maxima at 160kms-1 for the outward velocity, 5 × 104 km for the height, 8 × 103 km for the width, and about 10min for the lifetime of the jets. We also present the first statistical study of jet transverse motions, which obtained transverse velocities of 0-35kms-1. These values were obtained on the basis of a larger (in terms of frequency) and better sampled set of events than what was previously statistically studied (Shimojo et al. 1996, PASJ, 48, 123). The results were made possible by the unique characteristics of XRT. We describe the methods used to determine the characteristics and set some future goals. We also show that despite some possible selection effects, jets preferably occur inside the polar coronal holes. Title: Hinode Observations of the Onset Stage of a Solar Filament Eruption Authors: Sterling, Alphonse C.; Moore, Ronald L.; Berger, Thomas E.; Bobra, Monica; Davis, John M.; Jibben, Patricia; Kano, Ryohei; Lundquist, Loraine L.; Myers, D.; Narukage, Noriyuki; Sakao, Taro; Shibasaki, Kiyoto; Shine, Richard A.; Tarbell, Theodore D.; Weber, Mark Bibcode: 2007PASJ...59S.823S Altcode: We used Hinode X-Ray Telescope (XRT) and Solar Optical Telescope (SOT) filtergraph (FG) Stokes-V magnetogram observations, to study the early onset of a solar eruption that includes an erupting filament that we observe in TRACE EUV images. The filament undergoes a slow rise for at least 20min prior to its fast eruption and strong soft X-ray (SXR) flaring; such slow rises have been previously reported, and the new Hinode data elucidate the physical processes occurring during this period. XRT images show that during the slow-rise phase, an SXR sigmoid forms from apparent reconnection low in the sheared core field traced by the filament, and there is a low-level intensity peak in both EUV and SXRs during the slow rise. MDI and SOT FG Stokes-V magnetograms show that the pre-eruption filament is along a neutral line between opposing-polarity enhanced network cells, and the SOT magnetograms show that these opposing fields are flowing together and canceling for at least six hours prior to eruption. From the MDI data we measured the canceling network fields to be ∼ 40G, and we estimated that ∼ 1019 Mx of flux canceled during the five hours prior to eruption; this is only ∼ 5% of the total flux spanned by the eruption and flare, but apparently its tether-cutting cancellation was enough to destabilize the sigmoid field holding the filament and resulted in that field's eruption. Title: Fine Structures of Solar X-Ray Jets Observed with the X-Ray Telescope aboard Hinode Authors: Shimojo, Masumi; Narukage, Noriyuki; Kano, Ryohei; Sakao, Taro; Tsuneta, Saku; Shibasaki, Kiyoto; Cirtain, Jonathan W.; Lundquist, Loraine L.; Reeves, Katherine K.; Savcheva, Antonia Bibcode: 2007PASJ...59S.745S Altcode: The X-Ray Telescope (XRT) aboard Hinode has revealed the fine structure of solar X-ray jets. One of the fine structures observed by XRT is an expanding loop. The loop appeared near the footpoint of the jet when footpoint brightening was observed. Additionally, we have found that the X-ray jets began just after the expanding loop ``breaks''. Other fine structures discovered by XRT are thread-like features along the axis of the jets. XRT has shown that these thread structures compose the cross-section of jets. The fine structures and their motions strongly support an X-ray jet model based on magnetic reconnection, and also suggest that we must consider the three-dimensional configuration of the magnetic field to understand the jet phenomenon. We also investigated the reverse jet associated with the X-ray jet in the quiet Sun, and propose that the reverse jet is produced by heat conduction, or a MHD wave subsequent to the main jet. Title: Evolution of the Sheared Magnetic Fields of Two X-Class Flares Observed by Hinode/XRT Authors: Su, Yingna; Golub, Leon; van Ballegooijen, Adriaan; Deluca, Edward E.; Reeves, Kathy K.; Sakao, Taro; Kano, Ryouhei; Narukage, Noriyuki; Shibasaki Kiyoto Bibcode: 2007PASJ...59S.785S Altcode: We present multi-wavelength observations of the evolution of the sheared magnetic fields in NOAA Active Region 10930, where two X-class flares occurred on 2006 December 13 and December 14, respectively. Observations made with the X-ray Telescope (XRT) and the Solar Optical Telescope (SOT) aboard Hinode suggest that the gradual formation of the sheared magnetic fields in this active region is caused by the rotation and west-to-east motion of an emerging sunspot. In the pre-flare phase of the two flares, XRT shows several highly sheared X-ray loops in the core field region, corresponding to a filament seen in the TRACE EUV observations. XRT observations also show that part of the sheared core field erupted, and another part of the sheared core field stayed behind during the flares, which may explain why a large part of the filament is still seen by TRACE after the flare. About 2-3 hours after the peak of each flare, the core field becomes visible in XRT again, and shows a highly sheared inner and less-sheared outer structure. We also find that the post-flare core field is clearly less sheared than the pre-flare core field, which is consistent with the idea that the energy released during the flares is stored in the highly sheared fields prior to the flare. Title: An On-Orbit Determination of the On-Axis Point Spread Function of the Hinode X-Ray Telescope Authors: Weber, Mark; Deluca, Edward E.; Golub, Leon; Cirtain, Jonathan; Kano, Ryouhei; Sakao, Taro; Shibasaki, Kiyoto; Narukage, Noriyuki Bibcode: 2007PASJ...59S.853W Altcode: The Hinode X-ray Telescope provides unprecedented observations of the solar corona in X-rays, due in part to its fine resolution. The X-ray point spread function (PSF) was measured before launch at the NASA X-ray Calibration Facility to have a FWHM of 0.8''. This paper describes the work to verify the PSF measurements using on-orbit observations of planetary transits and solar eclipses. Analysis of a Mercury transit gives a PSF FWHM = 1.0" ± 0.12". Title: Plans to Observe Flare-Associated Waves with Solar-B Authors: Narukage, N. Bibcode: 2007ASPC..369..205N Altcode: The textit{Solar-B} satellite has three scientific instruments: the Solar Optical Telescope (SOT), the X-ray Telescope (XRT) and the EUV Imaging Spectrograph (EIS). We expect SOT, XRT, and EIS to detect the origin of Moreton waves, coronal X-ray waves, and line-of-sight velocity of waves, respectively. In preparation for Solar-B, we examine the detectable possibility of waves with these telescopes and suggest methods for observation. Title: The Dynamics Of Fine Structures In Solar X-ray Jets Authors: Shimojo, Masumi; Narukage, N.; Kano, R.; Sakao, T.; Tsuneta, T.; Cirtain, J. W.; Lundquist, L. L.; Deluca, E. E.; Golub, L. Bibcode: 2007AAS...210.9422S Altcode: 2007BAAS...39Q.221S The X-ray telescope(XRT) aboard HINODE satellite has the great spatial/time resolution in X-ray range. And, the observations using XRT have revealed the fine structures of solar corona. From the observations, we found the fine thread structures in the X-ray jets and the structures move dynamically like wave. We also found that some X-ray jets start just after small loop expansion in the footpoint brightening. The observation results suggest that the reconnection process X-ray jets is very similar to that in large flares. Title: Hinode Data Calibration For Precise Image Co-alignment: XRT vs. SOT Authors: Shimizu, Toshifumi; DeLuca, E. E.; Lundquist, L.; Sakao, T.; Kubo, M.; Narukage, N.; Kano, R.; Katsukawa, Y.; Ichimoto, K.; Suematsu, Y.; Tsuneta, S.; Tarbell, T.; Shine, D.; Hinode Team Bibcode: 2007AAS...210.9417S Altcode: 2007BAAS...39Q.220S From late October in 2006, Hinode solar optical telescope (SOT) has started to produce series of 0.2-0.3 arcsec visible-light images, revealing dynamical behaviors of solar magnetic fields on the solar surface. Simultaneously, Hinode X-ray telescope (XRT) has been providing 1 arcsec resolution X-ray images of the solar corona, giving the location of heating and dynamics occuring in the corona. Precise image co-alignment of SOT data on XRT data with sub-arcsec accuracy is required to provide new information regarding connecting the corona to the photosphere. This presentation will give an introduction of Hinode between-telescopes' image co-alignment to SPD participants. For active region observations with sunspots, sunspots can be used as fiducial to co-align the data from the two telescopes each other. Satellite jitter in order of 1 arcsec or less is included in the series of XRT data, whereas image stabilization system (correlation tracker) removes the satellite jitter from the series of SOT images. Telescope pointings show orbital variation in order of a few arcsec, which can be well predicted from Hinode orbit information. Modeling co-alignment is under study and it is the only precise method for quiet Sun and limb observations. Title: Coronal Temperature Diagnostics With Hinode X-ray Telescope Authors: Narukage, Noriyuki; Sakao, T.; Kano, R.; Shimojo, M.; Tsuneta, S.; Kosugi, T.; Deluca, E. E.; Golub, L.; Weber, M.; Cirtain, J.; Japan-US X-Ray Telescope Team Bibcode: 2007AAS...210.6304N Altcode: 2007BAAS...39..172N An X-ray telescope (XRT) on board HINODE satellite observes the Sun in X-rays with high special resolution (1arcsec 730km on solar the disk). This telescope has 9 X-ray filters with different temperature responses. Using these filters, the XRT can detect the coronal plasma with a wide temperature range from less than 1MK to more than 10MK. Moreover, based on observations with more than 2 filters, we can estimate the coronal temperature. In this paper, we use the filter ratio method for coronal temperature diagnostics. Using this method, we can easily estimate the averaged temperature of the coronal plasma along the line-of-sight. This method has been used frequently in the past, but the high quality XRT data give us temperature maps with unprecedented accuracy and resolution. The XRT usually takes the full Sun images with 2 kinds of filters 4 times a day. Using this data and filter ratio method, we can obtain full Sun temperature maps with high special resolution. In our analysis, we can derive reliable temperatures not only in active regions but also in quiet regions and coronal holes. This map can be created with the data set of one synoptic observation. This means that we can obtain 4 maps a day. The result is a full Sun temperature movie that gives us an unprecedented view of the time evolution of solar temperature. In this meeting, we will show the full Sun temperature movie and our coronal temperature analysis results. Title: Continuous Upflow of Plasmas at the Edge of an Active Region as Revealed by the X-ray Telescope (XRT) aboard Hinode Authors: Sakao, Taro; Kano, R.; Narukage, N.; Kotoku, J.; Bando, T.; DeLuca, E. E.; Lundquist, L. L.; Golub, L.; Kubo, M.; Katsukawa, Y.; Tsuneta, S.; Hara, H.; Matsuzaki, K.; Shimojo, M.; Shibasaki, K.; Shimizu, T.; Nakatani, I. Bibcode: 2007AAS...210.7205S Altcode: 2007BAAS...39Q.179S We present X-ray imaging observations with Hinode X-Ray Telescope (XRT) of an active region NOAA AR 10942 made in the period of 20-22 February 2007. A prominent feature that drew our particular attention is that there revealed continuous upflow of soft-X-ray-emitting plasmas along apparently-open field lines towards the outer corona emanating from the edge of the active region.

The field lines are originated from an ensamble of small spots of following polarity, and are located at a border between the active region and an adjacent equatorial coronal hole(s) located to the east. The upflow was observed to be continuous throughout the three days of observation intervals with projected velocity of 140 km/s, accompanied with undulating motion of the field lines.

We assert that these upflowing plasmas would be a possible source of slow solar wind material, which supports a foresighted notion which grew out of interplanetary scintillation observations that slow solar wind most likely has its origin in the vicinity of active regions with large flux expansion (Kojima et al. 1999).

A preliminaty analysis indicates that the temperature of the upflowing material near the base of the field lines is 1.3 MK with number density of 2 × 109 /cm3. Assuming that all the material is to escape to the interplanetary space, this leads to a mass loss rate of 2 × 1011 g/s which amounts to a good fraction of the total mass loss rate for solar wind. It is noteworthy that, even apart from this unique upflow, we see continuous (up)flows of plasmas anywhere around (surrounding) the active region.

Details of the upflow will be presented and their possible implication to slow solar wind discussed. Title: Structure and Coronal Activity around Filament Channels Observed with Hinode XRT And TRACE Authors: Lundquist, Loraine L.; van Ballegooijen, A. A.; Reeves, K. K.; Sakao, T.; DeLuca, E. E.; Narukage, N.; Kano, R. Bibcode: 2007AAS...210.9427L Altcode: 2007BAAS...39..221L The combination of multi-wavelength, high resolution, high cadence data from the Hinode X-Ray Telescope (XRT) and the Transition Region And Coronal Explorer (TRACE) give an unprecedented view of solar active region dynamics and coronal topology. We focus on examples of filament structures observed by TRACE and XRT in December 2006 and February 2007. Co-alignment of observations in these two instruments yields a striking picture of the coronal structures, with loops lying both along and above the filament. Overlying loops exhibit remarkable dynamics while the filament lies dormant, and numerous x-point and triple-leg structures undergo repeated brightenings. We also employ magnetic field data from SOT and from SOLIS to compare a non-linear force-free model of the coronal magnetic field with the observed loops. Title: Temperature Structures Above Coronal Hole and Quiet Sun Authors: Kano, Ryouhei; Sakao, T.; Narukage, N.; Kotoku, J.; Bando, T.; DeLuca, E. E.; Lundquist, L.; Golub, L.; Tsuneta, S.; Hara, H.; Shibasaki, K.; Shimojo, M. Bibcode: 2007AAS...210.9436K Altcode: 2007BAAS...39..223K The X-ray Telescope (XRT) on board Hinode satelite has the capability to derive the temperature structure in the solar corona. We present the hieght dependence of the temperature above the limb. Because X-ray intensity above the limb is so faint, it is important to estimate the scattered light from disk corona. The eclipses happened on February 17 and March 19 in 2007 at Hinode orbit. On February 17, we took X-ray images above the south polar coronal hole, while Moon passed it. On March 19, we took the data for quiet Sun in the same way.

We can estimated the scattered light from the eclipse data, and derived the scatter-free X-ray images above the solar limb. In this meeting, we will present the temperatures above coronal hole and quiet Sun, based on the eclipse data. Title: Magnetic activity and the solar corona: first results from the Hinode satellite . Authors: Reale, Fabio; Parenti, Susanna; Reeves, Kathy K.; Weber, Mark; Bobra, Monica G.; Barbera, Marco; Kano, Ryohei; Narukage, Noriyuki; Shimojo, Masumi; Sakao, Taro; Peres, Giovanni; Golub, Leon Bibcode: 2007MmSAI..78..591R Altcode: The structure, dynamics and evolution of the solar corona are governed by the magnetic field. In spite of significant progresses in our insight of the physics of the solar corona, several problems are still under debate, e.g. the role of impulsive events and waves in coronal heating, and the origin of eruptions, flares and CMEs. The Hinode mission has started on 22 september 2006 and aims at giving new answers to these questions. The satellite contains three main instruments, two high resolution telescopes, one in the optical and one in the X-ray band, and an EUV imaging spectrometer. On the Italian side, INAF/Osservatorio Astronomico di Palermo has contributed with the ground-calibration of the filters of the X-ray telescope. We present some preliminary mission results, with particular attention to the X-ray telescope data. Title: Statistical Analysis of Reconnection Inflows in Solar Flares Observed with SOHO EIT Authors: Narukage, Noriyuki; Shibata, Kazunari Bibcode: 2006ApJ...637.1122N Altcode: We report observations of reconnection inflows in extreme ultraviolet (EUV) Fe XII λ195 images with the Extreme Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory (SOHO). Yokoyama and colleagues reported the first example observed on 1999 March 18. We survey the EIT data from 1996 to 2000 and find six new inflow events. We measure the inflow velocity vinflow for each event and find that vinflow is about 2.6-38 km s-1. Furthermore, using the six EIT inflow events observed simultaneously with Yohkoh SXT (including the Yokoyama event), we calculate the reconnection rate as MA≡vinflow/vA=0.001-0.07. It is also found that the plasmoid ejection and/or coronal mass ejection (CME) are closely related to the inflow. The velocity of the CME exhibits a correlation with the inflow velocity. Title: Magnetic Fields and Intensity Changes in Coronal Dimming Regions Authors: Attrill, G. D. R.; Narukage, N.; Shibata, K.; Harra, L. K. Bibcode: 2005ESASP.596E..11A Altcode: 2005ccmf.confE..11A No abstract at ADS Title: Observations of Flare-Associated Waves with SolarB Authors: Narukage, N.; Shibata, K. Bibcode: 2004ASPC..325..389N Altcode: In Hα, a flare-associated chromospheric wave (called a Moreton wave) was discovered in 1960, and after that such waves are sometimes observed. Uchida (1968, 1974) identified the Moreton wave as the intersection of a coronal MHD fast-mode shock and the chromosphere. Recently, the Soft X-ray Telescope (SXT) on board Yohkoh observed coronal wave-like disturbances (X-ray waves). Narukage et al. (2002, 2004) showed two X-ray waves are MHD fast-mode shock, i.e. coronal counterparts of the Moreton waves. The SolarB has Solar Optical Telescope (SOT), X-Ray Telescope (XRT) and EUV Imaging Spectrometer (EIS) on board and will be launched in 2006. We expect SOT, XRT and EIS will detect chromospheric Moreton waves, coronal X-ray waves and line-of-sight velocity of waves, respectively. In preparation for SolarB, we examine the detectable possibility of waves with these telescopes and suggest methods for observation. Title: Filament Oscillations and Moreton Waves Associated with EIT Waves Authors: Okamoto, Takenori J.; Nakai, Hidekazu; Keiyama, Atsushi; Narukage, Noriyuki; UeNo, Satoru; Kitai, Reizaburo; Kurokawa, Hiroki; Shibata, Kazunari Bibcode: 2004ApJ...608.1124O Altcode: In this paper we compare EUV Imaging Telescope (EIT) waves with simultaneous phenomena seen in Hα in order to address the question of what an EIT wave is. We surveyed the events associated with solar flares larger than GOES M-class in 1999-2002. The Hα data are taken with the Flare-monitoring Telescope (FMT) at the Hida Observatory of Kyoto University. Among 14 simultaneous observations of EIT waves and Hα, 11 were found to have filament eruptions, three were associated with Moreton waves, and one was found to have only filament oscillations. This shows that we cannot see clear wave fronts in Hα even if EIT waves exist, but that it is possible to recognize invisible waves by means of filament oscillations. The nature of filament oscillations and Moreton waves associated with EIT waves is examined in detail, and it is found that the filament oscillations were caused by EIT waves. Title: Moreton waves observed at Hida Observatory Authors: Narukage, Noriyuki; Eto, Shigeru; Kadota, Miwako; Kitai, Reizaburo; Kurokawa, Hiroki; Shibata, Kazunari Bibcode: 2004IAUS..223..367N Altcode: 2005IAUS..223..367N Moreton waves are flare-associated waves observed to propagate across the solar disk in Halpha, especially in the wing of Halpha. The Flare Monitoring Telescope at Hida Observatory of Kyoto University observed 12 events associated with flare waves (i.e., Moreton waves and/or filament oscillations) in Halpha from 1997 to 2002. We review our studies of Moreton waves based on these observations; relation between EIT wave and Moreton wave (Eto et al. 2002),simultaneous observation with X-ray wave (Narukage et al. 2002),three dimensional structure of flare-associated wave (Narukage et al. 2004),relation between Moreton waves and filament eruptions. Title: Statistical analysis of reconnection inflows in solar flares Authors: Narukage, N.; Shibata, K. Bibcode: 2004cosp...35.3696N Altcode: 2004cosp.meet.3696N Solar flare is an explosion on the solar surface and releases huge energy in a short time. It is widely believed that the energy is stored in magnetic field and the flare is caused by magnetic reconnection. Yohkoh, a Japanese solar X-ray satellite launched in 1991, discovered various evidence of the magnetic reconnection, e.g. cusp shaped loops, plasmoid ejections, and etc. The reconnection model has been established at least phenomenologically by Yohkoh. However, the inflow, which is predicted by the reconnection theory, has not been discovered, and it remains mystery. In 2000, Yokoyama et al. discovered such reconnection inflow in a solar flare observed with SOHO/EIT, but no other observation of reconnection inflow has been reported until now. The generality of inflow remains doubtful. We surveyed the reconnection inflow in the full Sun movies taken with SOHO/EIT and discovered 13 inflows. We measured the line-of-sight velocity of the inflows using SOHO/EIT images, the angle between magnetic neutral line and line-of-sight direction in the inflows using SOHO/MDI images, and the energy release rate of the flares associated with the inflows using Yohkoh/SXT images. Based on this results, we estimated some physical quantities of the inflows, e.g. the real inflow velocity and reconnection rate. This result is conclusive evidence of reconnection and the clue to the solution of flare mechanism. Title: Relation between a Moreton Wave and an EIT Wave Observed on 1997 November 4 Authors: Eto, Shigeru; Isobe, Hiroaki; Narukage, Noriyuki; Asai, Ayumi; Morimoto, Taro; Thompson, Barbara; Yashiro, Seiji; Wang, Tongjiang; Kitai, Reizaburo; Kurokawa, Hiroki; Shibata, Kazunari Bibcode: 2002PASJ...54..481E Altcode: We consider the relationship between two flare-associated waves, a chromospheric Moreton wave and a coronal EIT wave, based on an analysis of an X-class flare event in AR 8100 on 1997 November 4. A Moreton wave was observed in Hα + 0.8 Å, and Hα - 0.8 Å with the Flare-Monitoring Telescope (FMT) at the Hida Observatory. An EIT wave was observed in EUV with the Extreme ultraviolet Imaging Telescope (EIT) on board SOHO. The propagation speeds of the Moreton wave and the EIT wave were approximately 715 km s-1 and 202 km s-1, respectively. The times of visibility for the Moreton wave did not overlap those of the EIT wave, but the continuation of the former is indicated by a filament oscillation. Data on the speed and location clearly show that the Moreton wave differed physically from the EIT wave in this case. The Moreton wave preceded the EIT wave, which is inconsistent with an identification of the EIT wave with a fast-mode MHD shock. Title: Simultaneous Observation of a Moreton Wave on 1997 November 3 in Hα and Soft X-Rays Authors: Narukage, N.; Hudson, H. S.; Morimoto, T.; Akiyama, S.; Kitai, R.; Kurokawa, H.; Shibata, K. Bibcode: 2002ApJ...572L.109N Altcode: We report the observation of a Moreton wave in Hα (line center and +/-0.8 Å) with the Flare Monitoring Telescope at the Hida Observatory of Kyoto University at 4:36-4:41 UT on 1997 November 3. The same region (NOAA Active Region 8100) was simultaneously observed in soft X-rays with the soft X-ray telescope on board Yohkoh, and a wavelike disturbance (``X-ray wave'') was also found. The position of the wave front as well as the direction of propagation of the X-ray wave roughly agree with those of the Moreton wave. The propagation speeds of the Moreton wave and the X-ray wave are about 490+/-40 and 630+/-100 km s-1, respectively. Assuming that the X-ray wave is an MHD fast-mode shock, we can estimate the propagation speed of the shock, on the basis of MHD shock theory and the observed soft X-ray intensities ahead of and behind the X-ray wave front. The estimated fast shock speed is 400-760 km s-1, which is in rough agreement with the observed propagation speed of the X-ray wave. The fast-mode Mach number of the X-ray wave is also estimated to be about 1.15-1.25. These results suggest that the X-ray wave is a weak MHD fast-mode shock propagating through the corona and hence is the coronal counterpart of the Moreton wave. Title: Reconnection Rate in the Decay Phase of a Long Duration Event Flare on 1997 May 12 Authors: Isobe, Hiroaki; Yokoyama, Takaaki; Shimojo, Masumi; Morimoto, Taro; Kozu, Hiromichi; Eto, Shigeru; Narukage, Noriyuki; Shibata, Kazunari Bibcode: 2002ApJ...566..528I Altcode: Recent analyses of long duration event (LDE) flares indicate successive occurrences of magnetic reconnection and resultant energy release in the decay phase. However, quantitative studies of the energy release rate and the reconnection rate have not yet been made. In this paper we focus on the decay phase of an LDE flare on 1997 May 12 and derive the energy release rate H and the reconnection rate MA=vin/vA, where vin is the inflow velocity and vA is the Alfvén velocity. For this purpose, we utilize a method to determine vin and the coronal magnetic field Bcorona indirectly, using the following relations:H=2B2corona/4πvinAr,Bcoronavin=Bfootvfoot,where Ar, Bfoot, and vfoot are the area of the reconnection region, the magnetic field strength at the footpoints, and the separation velocity of the footpoints, respectively. Since H, Ar, vfoot, and Bfoot are obtained from the Yohkoh Soft X-Ray Telescope data and a photospheric magnetogram, vin and Bcorona can be determined from these equations. The results are as follows: H is ~1027 ergs s-1 in the decay phase. This is greater than 1/10th of the value found in the rise phase. MA is 0.001-0.01, which is about 1 order of magnitude smaller than found in previous studies. However, it can be made consistent with the previous studies under the reasonable assumption of a nonunity filling factor. Bcorona is found to be in the range of 5-9 G, which is consistent with both the potential extrapolation and microwave polarization observed with the Nobeyama Radioheliograph. Title: Multi-wavelength Observations of a Moreton Wave on 2000 March 3 Authors: Narukage, N.; Morimoto, T.; Kitai, R.; Kurokawa, H.; Shibata, K. Bibcode: 2002aprm.conf..449N Altcode: Moreton waves are flare-associated waves observed to propagate across the solar disk in Hα (Moreton, 1960). Such waves have been identified as the intersections of a coronal fast-mode shock fronts and the chromosphere (Uchida, 1968). We report the observation of a Moreton wave in Hα (line center and ± 0.8 Å) with the Flare Monitoring Telescope (FMT) at the Hida Observatory of Kyoto University on 2000 March 3. The same region (NOAA 8882) was simultaneously observed in soft X-rays with the soft X-ray Telescope (SXT) on board Yohkoh, and a coronal wave-like disturbance (``X-ray wave") was also found. The region (NOAA 8882) is near the solar limb. Hence the chromospheric Moreton wave propagated on the solar disk at a speed of 1050 km/s, whereas the coronal X-ray wave propagated towards the outer corona at 1300 km/s. We identified the X-ray wave as an MHD fast-mode shock, i.e. a coronal counterpart of the Moreton wave, using MHD shock theory and the observed soft X-ray intensities (Narukage et al., 2002). On the basis of this result, the propagation of these two waves indicates the 3-dimensional structure of the flare-associated shock wave. This event is the first observation of the 3-d structure of the shock. Moreover, a type II radio burst and a coronal mass ejection (CME) were also observed simultaneously. The shock speed given by the type II radio burst is 1150 km/s. The CME propagated at a speed of 800 km/s. A basic component of CME is a density enhancement, and the shock preceding the CME propagates roughly 1.5 times faster than the CME, in this case at 1200 km/s. Title: Multi-Wavelength Observation of A Moreton Wave on November 3, 1997 Authors: Narukage, N.; Shibata, K.; Hudson, H. S.; Eto, S.; Isobe, H.; Asai, A.; Morimoto, T.; Kozu, H.; Ishii, T. T.; Akiyama, S.; Kitai, R.; Kurokawa, H. Bibcode: 2002mwoc.conf..295N Altcode: No abstract at ADS Title: Statistical Study of the Reconnection Rate in Solar Flares Authors: Isobe, H.; Morimoto, T.; Eto, S.; Narukage, N.; Shibata, K. Bibcode: 2002mwoc.conf..171I Altcode: The soft X-ray telescope (SXT) aboard Yohkoh has established that the driving mechanism of solar flares is magnetic reconnection. However, the physics of reconnection has not been clarified. One of the current puzzles is: what determines the reconnection rateNULL The reconnection rate is defined as reconnected magnetic flux per unit time or equivalently the ratio of inflow speed into reconnection point to Alfven velocity in non-dimension, and is one of the most important physical quantities in reconnection physics. However, observations have not yet succeeded to statistically determine the reconnection rate because direct observation of reconnection inflow and coronal magnetic field is difficult. In this poster we present a method to determine the reconnection rate from observational data, which use the following relations: H = frac B2 4pi vinL2 vinB = vfootBfoot. Here H, L, vfoot and Bfoot are respectively the flare heating rate, size of the flare arcade, separation velocity of the two ribbon, and magnetic field strength of the foot points. Since these four quantities can be obtained from observational data, the relations above give the inflow velocity vin and coronal magnetic field B, and thus the reconnection rate can be determined. Appling this method to many flare observations, we will determine the reconnection rate in solar flares statistically. A preliminary result is presented. Title: Simultaneous observations of Moreton waves in Hα and Soft X-ray Authors: Narukage, N.; Hudson, H.; Morimoto, T.; Kitai, R.; Kurokawa, H.; Shibata, K. Bibcode: 2002cosp...34E1337N Altcode: 2002cosp.meetE1337N Moreton waves are flare-associated waves observed to propagate across the solar disk in H (Moreton, 1960). Such waves have been identified as the intersections of a coronal fast-mode shock fronts and the chromosphere (Uchida, 1967). We report the two observations of Moreton waves in H (line center and +/- 0.8 A) with the Flare Monitoring Telescope (FMT) at the Hida Observatory of Kyoto University. The both events were simultaneously observed in soft X-rays with the Soft X-ray Telescope (SXT) on board Yohkoh, and wave-like disturbances ("X-ray wave") were also found. One event occurred in solar-disk on November 3, 1997, the other near solar limb on March 3, 2000. Assuming that the X-ray waves are the MHD fast shocks, we can estimate the propagation speeds of the shocks, based on the MHD shock theory and the observed soft X-ray intensities ahead and behind the X-ray wave fronts. It is found that the estimated fast shock speeds are in rough agreement with the observed propagation speeds of the X-ray waves. The fast mode Mach numbers of the X-ray waves are also estimated. These results suggest that the X-ray waves are MHD fast shocks propagating through the corona and hence are the coronal counterparts of the Moreton waves. Title: Observations of Moreton Waves and EIT Waves Authors: Shibata, K.; Eto, S.; Narukage, N.; Isobe, H.; Morimoto, T.; Kozu, H.; Asai, A.; Ishii, T.; Akiyama, S.; Ueno, S.; Kitai, R.; Kurokawa, H.; Yashiro, S.; Thompson, B. J.; Wang, T.; Hudson, H. S. Bibcode: 2002mwoc.conf..279S Altcode: The Moreton wave is a flare-associated wave observed in H alpha, and is now established to be a fast mode MHD shock emitted from the flare, but the physical mechanism to create the wave is still puzzling. On the other hand, the EIT wave is a newly discovered flare-associated wave observed in EUV with the Extreme ultraviolet Imaging Telescope (EIT) aboard SOHO, and in this case, not only its origin but also its physical property are both puzzling. We study the relationship of these two flare-associated waves, Moreton waves and EIT waves, by analyzing 4 events observed on Nov. 3 and 4, 1997, Aug. 8, 1998, and Mar. 3, 2000 (Narukage et al. 2001). The Moreton waves were observed in Ha, Ha+0.8A and Ha-0.8A with the Flare Monitoring Telescope (FMT) at the Hida Observatory of Kyoto University, while the EIT waves were observed with SOHO/EIT. In the typical case associated with an X-class flare in AR 8100 on 4 November 1997 (Eto et al. 2001) the propagation speeds of the Moreton wave and the EIT wave were approximately 780 km/s and 200 km/s respectively. The data on speed and location show clearly that the Moreton wave differs physically from the EIT wave in this case. The detailed analyses of the other events (Nov. 3, 1997, Aug. 8, 1998, and Mar. 3, 2000) will also be presented, with Yohkoh/SXT data in the lucky case.