Study of the Polarimetric Performance of a Si/CdTe Semiconductor Compton Camera for the Hitomi Satellite
Abstract
Gamma-ray polarization offers a unique probes into the geometry of the gamma-ray emission process in celestial objects. The Soft Gamma-ray Detector (SGD) onboard the X-ray observatory Hitomi is a Si/CdTe Compton camera and is expected to be an excellent polarimeter, as well as a highly sensitive spectrometer due to its good angular coverage and resolution for Compton scattering. A beam test of the final-prototype for the SGD Compton camera was conducted to demonstrate its polarimetric capability and to verify and calibrate the Monte Carlo simulation of the instrument. The modulation factor of the SGD prototype camera, evaluated for the inner and outer parts of the CdTe sensors as absorbers, was measured to be 0.649--0.701 (inner part) and 0.637--0.653 (outer part) at 122.2 keV and 0.610--0.651 (inner part) and 0.564--0.592 (outer part) at 194.5 keV at varying polarization angles with respect to the detector. This indicates that the relative systematic uncertainty of the modulation factor is as small as ~3%.
Keywords
Cite
@article{arxiv.1610.05433,
title = {Study of the Polarimetric Performance of a Si/CdTe Semiconductor Compton Camera for the Hitomi Satellite},
author = {Junichiro Katsuta and Ikumi Edahiro and Shin Watanabe and Hirokazu Odaka and Yusuke Uchida and Nagomi Uchida and Tsunefumi Mizuno and Yasushi Fukazawa and Katsuhiro Hayashi and Sho Habata and Yuto Ichinohe and Takao Kitaguchi and Masanori Ohno and Masayuki Ohta and Hiromitsu Takahashi and Tadayuki Takahashi and Shin'ichiro Takeda and Hiroyasu Tajima and Takayuki Yuasa and Masayoshi Itou},
journal= {arXiv preprint arXiv:1610.05433},
year = {2016}
}
Comments
accepted for publication in NIMA