微通道板型X射线探测器的脉冲信号探测能力实验分析  

Experimental Analysis of Pulse Signal Detection Capability of the MCP X-ray Detector

作　　者：周庆勇 盛立志[4] 魏子卿[2,3] 刘思伟 陈琛[4] 姬剑锋 任红飞[2,3] 马高峰[1] 张彩红 孙鹏飞[7] ZHOU Qing-yong;SHENG Li-zhi;WEI Zi-qing;LIU Si-wei;CHEN Chen;JI Jian-feng;REN Hong-fei;MA Gao-feng;ZHANG Cai-hong;SUN Peng-fei(Geographic Spatial Information Institute,Information Engineering University,Zhengzhou 450052,China;State Key Laboratory of Geo-information Engineering,Xi’an 710054,China;Xi’an Research Institute of Surveying and Mapping,Xi’an 710054,China;Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710119,china;GNSS Center,Wuhan University,Wuhan 430079,China;Key Laboratory of Earthquake Geodesy,Institute of Seismology,China Earthquake Adminstration,Wuhan 430071,China;College of Geological Engineering and Surveying,Changan University,Xi’an 710054,China)

机构地区：[1]信息工程大学地理空间信息学院,郑州450052 [2]地理信息工程国家重点实验室,西安710054 [3]西安测绘研究所,西安710054 [4]中国科学院西安光学精密机械研究所,西安710119 [5]武汉大学GNSS中心,武汉430079 [6]中国地震局地震研究所地震大地测量重点实验室,武汉430071 [7]长安大学地质工程与测绘学院,西安710054

出　　处：《光子学报》2018年第9期169-179,共11页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.41304006,41374042,41574013,41374003);地理信息工程国家重点试验室开放研究基金(No.SKLGIE 2018-ZZ-3)资助。

摘　　要：为了掌握微通道板探测器的X射线脉冲信号观测能力,利用X射线脉冲星地面实验装置,开展了长时间的不同流强和不同背景噪声强度下的微通道板探测器脉冲信号探测实验,并建立了一套X射线探测器脉冲观测能力评估方法,推导出基于光子计时模式下X射线探测器的脉冲信号信噪比、脉冲轮廓相似度、脉冲到达时间精度和最小可探测功率的关系表达式.实验中,利用面积20cm^2的微通道板探测器开展了8组10 000s的实验,采集到有效观测数据,然后搜索最佳脉冲周期,重构观测脉冲轮廓,估计脉冲轮廓特征参数.实验表明,微通道板探测器具备良好的X射线脉冲信号观测与恢复能力,在较弱脉冲信号强度(光子流量密度为0.05ph/cm^2/s)和较强背景噪声(背景噪声强度是脉冲信号的16倍)下获取观测脉冲轮廓的信噪比、相似度、脉冲到达时间观测精度分别为35.73、88.38%、51.53μs和64.89、89.72%、29.24μs,验证了微通道板探测器具备一定的暗弱X射线脉冲星观测能力,且微通道板探测器的脉冲探测能力随着脉冲信号强度增加、背景噪声强度减弱、累积观测时间增加而提升.For analyzing the X-ray pulsed signal observation capability of micro-channel plate detector,a long-time experiment of micro-channel plate detectors under different radiation flux and different background noise was operated on the X-ray detector ground testing system.Meanwhile,a set of evaluation methods of pulse observation capability of X-ray detectors were established,the expressions of the signal-to-noise ratio,the correlation of pulse profile,the measurement accuracy of pulse arrival time,the minimum detectable power were derived based on the photon counting model.8 groups of 10 000 s X-ray photon time-of-arrival dataset were received by the 20 cm 2 micro-channel plate detectors.Then the effective observation data were dealt with,the pulse period of each dataset was gained,the observable pulse profile was replicated,and their characteristic parameters were estimated.The experimental result shows that the micro-channel plate detector has a good capability of X-ray pulse signal observation and reconstruction,the signal-to-noise ratio,the correlation of pulse profile,the measurement accuracy of pulse arrival time of the observed pulse profile are 35.73,88.38%,51.53μs at the low pulse signal flux(the X-photon flux density is 0.05 ph/cm^2/s),while those are 35.73,88.38%,51.53μs at strong background noise(the background noise is 16 times the intensity of the pulse signal).This result has revealed that the micro-channel plate detector has the observation ability of a certain faint X ray pulsar.The pulse detection capability of micro-channel plate detector is improved with the increase of the intensity of the pulse signal,the decrease of the background noise intensity and the increase of the accumulated observation time.

关 键 词：X射线探测 性能测试 微通道板探测器 地面测试系统 脉冲信号 X射线脉冲星模拟源 脉冲轮廓 背景噪声 

分 类 号：P172.2[天文地球—天文学] TL816[核科学技术—核技术及应用]