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ASTRO-H 衛星搭載の軟X線撮像検出器(SXI:Soft X-ray Imager) は軟X線望遠鏡(SXT : Soft X-ray Telescope) の焦点面に配置される。田の字型に配置された4 枚の大面積CCD 素子が、38 分角四方と、ASTRO-H 搭載検出器としては最も広い視野を構成し、0.4-12 keV のエネルギー帯域で撮像分光観測を行う。SXI のフロントエンド回路には、アナログデジタル混在ASIC (application-specic integrated circuit) を採用している。従来の個別回路部品で構成される信号処理回路を大幅に小型化、軽量化している。ASIC 単体での機能と性能、さらに放射線耐性の実証を完了した後、JAXA 集積回路仕様書に準拠したQCI(quality conformance inspection) 試験と、フライトモデル候補全数に対するバーンイン試験を実施した。特にバーンイン試験は、通電かつCCD の疑似信号を処理させた状態のダイナミックバーンイン試験を行った。+115C、200 時間の試験の前後で、入力等価雑音、積分非線形性、ゲインを測定した結果、供試体32 素子全てについて、故障や性能劣化がないことが確認された。この結果を基にフライトモデル8 素子が選定され、SXI カメラボディ内部の電子回路基板に実装された。, Soft X-ray Imager (SXI) is the primary imaging instrument on board the X-ray astronomical satellite ASTRO-H. The focal plane assembly consists of the four large-area P-channel CCDs abutted into a 2 × 2 array and the signal processing board including mixed-signal ASICs (applicationspecific integrated circuit). Given the focal length of 5.6 m, the four chips cover a region of 38’ × 38’ on the sky combined with the Soft X-ray Telescope. One of the advancements of SXI compared with conventional on board CCD cameras is the signal processing using mixed-signal ASICs with the function of the preamplifier and the analog-to-digital conversion. The dedicated design of the delta sigma modulators enables us to achieve high signal-to-noise ratio with the relatively small number of the transistors. It simultaneously processes the analog signals from the four readout nodes. After the verification of the performance such as the input equivalent noise, linearity, gain and radiation tolerance, we performed the quality conformance inspection test in accordance with the JAXA parts program, followed by the burn-in test for all the flight chip candidates. The dynamic burn-in test was carried out with the temperature of +115C in the duration of 200 hours to expose the initial malfunction in the mission. Pseudo CCD signals are fed into all the devices during the test. There was no trouble in functional point of view and the performance showed no change after the dynamic burn-in. The eight flight model chips have been selected and mounted on the signal processing board., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations

ASTRO-H, the new Japanese X-ray Astronomy Satellite following Suzaku, is an international X-ray mission which is currently planed for launch in 2013. ASTRO-H is a combination of wide band X-ray spectroscopy (3 - 80 keV) provided by multi-layer coating, focusing hard X-ray mirrors and hard X-ray imaging detectors, and high energy-resolution soft X-ray spectroscopy (0.3 - 10 keV) provided by thin-foil X-ray optics and a micro-calorimeter array. The mission will also carry an X-ray CCD camera as a focal plane detector for a soft X-ray telescope and a non-focusing soft gamma-ray detector. With these instruments, ASTRO-H covers very wide energy range from 0.3 keV to 600 keV. The micro-calorimeter system will be developed by international collaboration lead by lSAS/JAXA and NASA. The simultaneous broad bandpass, coupled with high spectral resolution of delta.E ca. 7 eV by the micro-calorimeter will enable a wide variety of important science themes to be pursued., Meeting Information: Astrophysics with All-Sky X-Ray observations: 3rd International MAXI Workshop (RIKEN, 10-12 June 2008)

We present results from monitoring the performance of the Suzaku XIS CCD sensors during the first three years of operation. Accumulated radiation damage has changed the gain of the XIS sensors as much as three percent and degraded the spectral resolution by as much as thirty percent as measured by the onboard X-ray calibration sources. The spatial non-uniformity of the XIS contamination has changed by a factor two as measured using bright Earth data. These trends are regularly updated at http://space.mit.edu/XIS/monitor., Meeting Information: The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science

We are planning to have a Formation Flying Astronomical Survey Telescope (FFAST) that will make a hard X-ray (less than or equal to 80 keV) imaging survey. Two small satellites(approximately 1 cu m), a telescope satellite and a detector satellite, will be placed into a circular 550km orbit and in formation flying that will be controlled the separation of 20 m +/- 10 cm. With a relative-circular orbit, we can select the scanning sky region arbitrarily; in the case of covering Omega approximately 1000 sq deg areas of sky, the detection limit of 0.1 mCrab will be achieved in two years. Hence, the FFAST will be able to fill the sensitivity gap of AGN surveys performed by ongoing and future hard X-ray missions., Meeting Information: The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science, 著者人数: 11人(含チーム1), Number of authors: 11

We present the analysis of Suzaku observations of the young open cluster Westerlund 2, which is filled with diffuse X-ray emission. We found that the emission consists of three thermal components or two thermal and one non-thermal components. The upper limit of the energy flux of the non-thermal component is smaller than that in the TeV band observed with H.E.S.S. This may indicate that active particle acceleration has stopped in this cluster, and that the accelerated electrons have already cooled. The gamma-ray emission observed with H.E.S.S. is likely to come from high-energy protons, which hardly cool in contrast with electrons. Metal abundances of the diffuse X-ray gas may indicate the explosion of a massive star in the past. The details of this study are presented in Fujita et al. (2009a)., Meeting Information: The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science

We have developed the X-ray CCD camera system for the Soft X-ray Imager (SXI) which will be launched as focal plane detectors of X-ray telescope onboard the Japanese 6th X-ray astronomical satellite, Astro-H. The X-ray CCD is back-illuminated (BI) CCD which has an Optical Blocking Layer (OBL) directly coating its X-ray illumination surface with Aluminum-Polyimide-Aluminum instead of Optical Blocking Filter (OBF). The X-ray CCD is affected by large doses of extreme ultraviolet (EUV) radiation from Earth sun-lit atmosphere (airglow) in orbit. To evaluate the performance of polyimide that cut off EUV, we measured the EUV transmission of both OBL and OBF at various energy range between 15 - 72 eV by utilizing beam line located at the Photon Factory in High Energy Accelerator Research Organization (KEK-PF) in this March and June, and obtained the EUV transmission to be 3% at 41 eV which is as same as expected transmission from the designed thickness of polyimide layer., Meeting Information: The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science, 著者人数: 22人, Number of authors: 22

We present a Suzaku observation of the narrow-line Seyfert 1 galaxy Ton S180. The hard X-ray spectra above 15 keV is obtained for the first time. Wide band X-ray spectra shows that soft excess and hard excess, and a broad iron emission line are found. The broad iron emission is centered on 6.7 keV and most likely fluorescent X-rays from the ionized matter. We consider that the hard excess is also the reflection from the ionized matter. Possible models to reproduce the soft X-ray excess are examined, and spectral variability is discussed., Meeting Information: The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science

We report current status of the timing calibration of the X-ray Imaging Spectrometer (XIS) on board Suzaku. The XIS is designed to be flexible enough and can be operated in various clocking modes. Since the absolute timing accuracy of the Hard X-ray Detector (HXD) was calibrated to be better than 360 microseconds, we calibrated the XIS timing accuracy referring to the HXD data. We employed Hercules X-1 and Cygnus X-1 for the calibration taking into account of the energy dependence of their time variations. We found no significant offset in the XIS time assignment in the normal mode (with burst/window options), whereas a marginal offset of 30 +/- 16 ms was found in the Parallel-Sum mode., Meeting Information: The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science