FOXSI 太陽硬X線観測ミッション
The Focusing Optics X-ray Solar Imager (FOXSI) is a NASA sounding rocket mission which will study particle acceleration and coronal heating on the Sun through unprecedented high-resolution imaging in the hard X-ray energy band (5-15 keV). With a combination of high-resolution focusing X-ray optics and fine-pitch imaging sensors, FOXSI will achieve superior sensitivity; two orders of magnitude better than that of the RHESSI satellite.

本研究室が開発しているFOXSI焦点面検出器のIEEE国際会議でのポスター発表(石川他, 2009)
To achieve such a sensitivity, we plan to use a fine-pitch Double-sided Si Strip Detector (DSSD) with a low-noise front-end ASIC as the FOXSI focal plane detector, which will fulfill the scientific requirements for the spatial resolution, energy resolution, lower threshold energy and time resolution. We have newly designed and fabricated a DSSD with a thickness of 500 μm and a dimension of 9.6 mm×9.6 mm, containing 128 strips separated by a pitch of 75 μm, which corresponds to 8”at the focal length of 2 m. The DSSD was successfully operated in a laboratory experiment under a temperature of -20 °C and a bias voltage of 260 V. The energy resolution was measured to be 1.0 keV (FWHM) at 14 keV, sufficient for the FOXSI mission requirement.