北京谱仪Ⅱ中性径迹测量误差的确定  

Study of Neutral Track Measurement at BESⅡ

作　　者：王君[1] 吕峰[1] 童国梁[1] 张长春[1] 洪涛[1] 袁建明[1] 徐晔[1] 

机构地区：[1]中国科学院高能物理研究所,北京100039

出　　处：《高能物理与核物理》2002年第2期116-121,共6页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金 ( 1 9991 4 80 );中国科学院重大及特别支持项目 (KJ95T -0 3)资助~~

摘　　要：选取辐射Bhabha样本 ,研究了北京谱仪Ⅱ (BESⅡ )桶部簇射计数器 (BSC)对中性径迹的沉积能量和空间位置的测量 ,定出了实际数据的测量误差 .并利用MonteCarlo产生的e+e- →γγ事例定出MC数据的能量及位置测量误差 .结果已用于BESⅡ运动学拟合 ,能改善物理分析结果 .The measurement errors of the deposited energy and position of neutral tracks in Barrel Shower Counter (BSC) of BESⅡ are investigated. The errors of energy and position of real data are determined by radiative Bhabha events, while the errors of Monte Carlo Data are determined by e +e -→γγ events. Then the corrections are tested by the selected ρπ sample, which shows better pull and Confidence Level distribution after the correction. The results are already applied to the kinematic fitting, which can improve the physics results at BESⅡ.

关 键 词：运动学拟合 簇射计数器 辐射Bhabha 北京谱仪Ⅱ 测量误差 中性径迹 沉积能量 空间位置 

分 类 号：O572.21[理学—粒子物理与原子核物理] TL817[理学—物理]