Soft gamma-ray detector for the ASTRO-H Mission
Soft gamma-ray detector for the ASTRO-H Mission
复制标题
用于 ASTRO-H 任务的软伽马射线探测器
DOI：
10.1117/12.925977
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
et al.
中科院分区：
文献类型：
--
作者：
S. Watanabe;et al.
ASTRO-H是日本宇宙航空研究开发机构的下一代X射线卫星，打算携带具有广泛能量覆盖范围和精密能量分辨率的仪器。软伽马射线探测器是ASTRO-H仪器之一，其特点是本底水平的宽能量带（60-600千电子伏），比轨道上现有仪器好10倍。SGD与ASTRO-H的硬X射线成像仪互补，覆盖5-80 keV的能量范围。SGD通过将康普顿相机方案与窄视场主动屏蔽相结合来实现低背景，其中康普顿运动学用于拒绝背景。SGD中的康普顿照相机是由硅和碲化镉（CdTe）传感器组成的混合半导体探测器系统。半导体传感器提供了良好的能量分辨率，并且由于对康普顿运动学的更好约束，它导致了良好的背景抑制能力。康普顿运动学的利用也使得SGD对伽马射线偏振敏感，为研究伽马射线发射过程的性质开辟了一个新的窗口。在本文中，我们将提出的SGD的详细设计和最终原型的开发和评估的结果。此外，我们还将根据原型的测量结果提出预期性能。
ASTRO-H is the next generation JAXA X-ray satellite, intended to carry instruments with broad energy coverage and exquisite energy resolution. The Soft Gamma-ray Detector (SGD) is one of ASTRO-H instruments and will feature wide energy band (60–600 keV) at a background level 10 times better than the current instruments on orbit. The SGD is complimentary to ASTRO-H’s Hard X-ray Imager covering the energy range of 5–80 keV. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield where Compton kinematics is utilized to reject backgrounds. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) sensors. Good energy resolution is afforded by semiconductor sensors, and it results in good background rejection capability due to better constraints on Compton kinematics. Utilization of Compton kinematics also makes the SGD sensitive to the gamma-ray polarization, opening up a new window to study properties of gamma-ray emission processes. In this paper, we will present the detailed design of the SGD and the results of the final prototype developments and evaluations. Moreover, we will also present expected performance based on the measurements with prototypes.