利用TOF的Q值进行粒子鉴别的研究  

Particle Identification with Pulse Amplitude of TOF Counter

作　　者：刘芳[1] 何康林[1] 孙胜森[1] 杨帆[1] 郑志鹏[1] 李金[1] 

机构地区：[1]中国科学院高能物理研究所

出　　处：《高能物理与核物理》2005年第8期781-786,共6页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金(19991480;90103002);中国科学院知识创新工程项目(U602)资助~~

摘　　要：飞行时间计数器(TOF)是北京谱仪(BESⅡ)中用于粒子鉴别的重要子探测器.当带电粒子击中TOF时,闪烁计数器同时测量粒子的飞行时间T和脉冲幅度Q.本文利用BESⅡ采集的双μ事例,对脉冲幅度Q进行了研究.利用J/ψ强子事例样本,给出了脉冲幅度最可几值Qmp随粒子βγ值的变化关系.这表明可以利用TOF测量的脉冲幅度Q值实现对粒子的鉴别.最后给出用脉冲幅度Q进行粒子鉴别的效率和误判率.Time of flight counter（TOF） is one of the main subdetectors of Beijing Spectrometer Ⅱ （ BES Ⅱ ） for identification of charge particles. Time of flight and pulse amplitude are measured from the time of flight counters, when the particle hits on the TOF. Based on Di-mu sample from BESⅡ , the correction of pulse amplitude Q is studied. Using the hadron sample of J/ψ, the relation between the corrected Pulse amplitude and βγ value is analyzed. A conclusion is that it is feasible to use the pulse amplitude Q0 of TOF to identify the particles. Finally the particle identification and mis-identificafion rate are given when the pulse amplitude is used to identify the particles.

关 键 词：飞行时间计数器 TOF 粒子鉴别 脉冲幅度 衰减长度 

分 类 号：O572.2[理学—粒子物理与原子核物理]