Analog rise-time discriminator for CdZnTe detector  

作　　者：Chuan-Hao Hu Guo-Qiang Zeng Liang-Quan Ge Shi-Long Wei Jian Yang Qiang Li Hong-Zhi Li 

机构地区：[1]Chengdu University of Technology, Chengdu 610059, China [2]National Ocean Technology Center, Tianjin 300112, China

出　　处：《Nuclear Science and Techniques》2017年第4期59-65,共7页核技术（英文）

基　　金：supported by the Natural Science Foundation of China(NSFC)(No.41474159);National High-tech R&D Program of China(863 Program)(Nos.2012AA061803 and 2014AA093403);Open Foundation of Applied Nuclear Techniques in Geosciences Key Laboratory of Sichuan Province(No.gnzds2014006)

摘　　要：Due to variable time for charge collection,energy resolution of nuclear detectors declines,especially compound semiconductor detectors like cadmium zinc telluride(CdZnTe) detector.To solve this problem,an analog rise-time discriminator based on charge comparison principle is designed.The reference charge signal after attenuation is compared with the deconvoluted and delayed current signal.It is found that the amplitude of delayed current signal is higher than that of the reference charge signal when rise time of the input signal is shorter than the discrimination time,thus generating gating signal and triggering DMCA(digital multi-channel analyzer) to receive the total integral charge signal.When rise time of the input signal is longer than discrimination time,DMCA remains inactivated and the corresponding total integral charge signal is abandoned.Test results show that combination of the designed rise-time discriminator and DMCA can reduce hole tailing of CdZnTe detector significantly.Energy resolution of the system is 0.98%@662 keV,and it is still excellent under high counting rates.Due to variable time for charge collection, energy resolution of nuclear detectors declines, especially compound semiconductor detectors like cadmium zinc telluride (CdZnTe) detector. To solve this problem, an analog rise-time discriminator based on charge comparison principle is designed. The reference charge signal after attenuation is compared with the deconvoluted and delayed current signal. It is found that the amplitude of delayed current signal is higher than that of the reference charge signal when rise time of the input signal is shorter than the discrimination time, thus generating gating signal and triggering DMCA (digital multi-channel analyzer) to receive the total integral charge signal. When rise time of the input signal is longer than discrimination time, DMCA remains inactivated and the corresponding total integral charge signal is abandoned. Test results show that combination of the designed rise-time discriminator and DMCA can reduce hole tailing of CdZnTe detector significantly. Energy resolution of the system is 0.98%@662 keV, and it is still excellent under high counting rates.

关 键 词：ANALOG rise-time DISCRIMINATOR CDZNTE detector Charge comparison PRINCIPLE 

分 类 号：TL81[核科学技术—核技术及应用]