GECAM能量响应及在轨本底模拟  

Energy response and in-flight background simulation for GECAM

作　　者：郭东亚[1] 彭文溪[1] 朱玥[1] 李刚[1] 廖进元 熊少林[1] 乔锐[1] 李新乔[1] 安正华[1] 徐岩冰[1] 杨生[1] 张大力[1] 孙希磊[1] GUO DongYa;PENG WenXi;ZHU Yue;LI Gang;LIAO JinYuan;XIONG ShaoLin;QIAO Rui;LI XinQiao;AN ZhengHua;XU YanBing;YANG Sheng;ZHANG DaLi;SUN XiLei(Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院高能物理研究所粒子天体物理重点实验室,北京100049

出　　处：《中国科学：物理学、力学、天文学》2020年第12期97-105,共9页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：中国科学院战略性先导科技专项(A类)(编号:XDA15360300,XDA15052700)资助项目。

摘　　要：GECAM卫星的主要科学目标是探测引力波伽马暴及其他高能暂现源,具有全天视场、高灵敏度、良好的定位精度和宽能段覆盖等特点.本文在构建GECAM整星质量模型的基础上,通过Geant4模拟得到了GECAM伽马射线探测器(GRD)的能量响应矩阵;并给出了在轨本底水平、本底能谱结构及组成成分的估计结果.模拟结果显示相比Fermi/GBM,GECAM不仅视场更大,而且在低能区具有更大的有效面积.同时根据在轨本底模拟结果可知:(1)单个GRD探头的平均在轨本底约为800 cps,其中宇宙弥散伽马射线本底占主导;(2)本底谱中存在三个特征峰,可用于在轨标定探测器的增益.The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM) is designed to detect gravitational wave gamma-ray bursts and other high-energy transient sources in the energy range of 6 ke V–5 Me V. It has the characteristics of all-sky field of view, high sensitivity, good positioning accuracy and wide band coverage. The mission consists of two satellites with each containing 25 Gamma-Ray Detectors(GRD) and 8 charged particle detectors.In this paper, the energy response matrix and in-flight background of each GECAM detector are obtained by Geant4 simulation. The simulation results show that the GECAM has stronger observation ability than the Fermi/GBM in lowenergy range. The average in-flight background of a single GRD is about 800 cps, and there are three characteristic peaks that can be used for on-orbit calibration.

关 键 词：伽马暴 Geant4模拟 能量响应矩阵 在轨本底 

分 类 号：TL816.2[核科学技术—核技术及应用] V474.1[航空宇航科学与技术—飞行器设计]