10th International "Hiroshima" Symposium on the Development and Application of Semiconductor Tracking Detectors, Xi'an, China

Soft X-ray quantum efficiency of X-ray CCD onboard ASTRO-H

26 Sept 2015, 19:57

1m

Multi-function Hall (International Conference Center (Nanyang Hotel))

POSTER Applications in Space, Medical, Biology, Material Sciences After dinner POSTER session, with drinks: (All presenters are requested/encouraged to attend their posters; All participants are requested to participate the session, with drinks!)

Speaker

Takayoshi Kohmura (Tokyo University of Science)

Description

We have developed X-ray CCD which was named Soft X-ray Imager (SXI) on onboard ASTRO-H which will launch in 2015. We employed the P-channel, back-illuminated (BI) type CCDs for SXI camera with a depletion layer thickness of 200um manufactured by Hamamatsu Photonics K.K. SXI CCD has high QE at the soft X-ray energy range below 2.0keV and thanks to its thick depletion layer, SXI enables to cover the wide X-ray energy range between 0.2-20.0keV. SXI CCD was coated with 100nm thick Al to block optical light which cause the noise for X-ray observation in space. This Al is the dead layer for BI CCD of SXI and absorbs the soft X-ray. Therefore, to determine the QE below 2keV precisely, it is necessary to measure the thickness of Al on the surface of CCD. We have carried out the measurement of QE below 2keV at the synchrotron facility in Japan, KEK photon factory. In this measurement, we employed slant incident method by changing X-ray incident angle to the X-ray CCD from 0 deg to 50 deg and compared the X-ray flux of each angle. In this paper, we will report the result of the soft X-ray QE of SXI.