JLab Hall-A库仑求和规则实验中气体契仑柯夫探测器刻度和截断效率研究(英文)  

Gas Cherenkov detector calibration and cut efficiency studyfor Coulomb sum rule experiment in JLab Hall-A

作　　者：闫新虎[1] 叶云秀[2] 吕海江[1] 蒋峰建[1] 朱鹏佳[2] 石瑛[1] 

机构地区：[1]黄山学院物理系,安徽黄山245041 [2]中国科学技术大学近代物理系,安徽合肥230026

出　　处：《中国科学技术大学学报》2013年第6期480-485,共6页JUSTC

基　　金：Supported by the National Natural Science Foundation of China(11135002,11275083);Natural Science Foundation ofAnhui Education Committee(KJ2012B179,KJ2011B164).

摘　　要：在库仑求和实验中,主要用JLab Hall-A里左臂和右臂上的气体契仑柯夫探测器区分背景粒子,它可以有效地从好电子样本中分离出主要背景粒子π.气体契仑柯夫探测器已经被很好地刻度,其中的10个球面镜道都已被刻度到统一值200.通过对该探测器信号的刻度修正,电子截断效率和π粒子拒绝效率的研究,即便在低动量区间,电子的截断效率和π的拒绝效率也分别好于99%和98.5%.经过刻度修正和效率分析后的气体契仑柯夫探测器可以为库仑求和实验的截面计算提供优秀的粒子鉴别效率.In Coulomb sum rule （CSR） experiment, the background which is mainly 7r can be separated efficiently from the good electron samples with the CO2 gas threshold Cherenkov detector for the left and right arms at HaI1-A in Jefferson Jlab （JLab）. The gas Cherenkov detector was calibrated well and the single photon electron peak of all ten channels were scaled to 200. The cut efficiency for selecting good electrons and pion rejection of the detector was analyzed. After applying the cut value equal to 300 on the summed ADC signals of the gas Cherenkov detector, the cut efficiency of electrons is better than 99G and the pion rejection is still better than 98.5% for low momentum setting. After the calibration and cut efficiency study, the gas Cherenkov detector can provide excellent particle identification for the cross section calculation of the CSR experiments.

关 键 词：库仑求和规则 刻度 截断效率 π拒绝 

分 类 号：O572.212[理学—粒子物理与原子核物理]