Decay vertex reconstruction and 3-dimensional lifetime determination at BESⅢ  

作　　者：徐敏 何康林 张子平 王贻芳 边渐鸣 曹国富 曹学香 陈申见 邓子艳 傅成栋 高原宁 韩磊 韩少卿 何苗 胡继峰 胡小为 黄彬 黄性涛 贾卢魁 季晓斌 李海波 李卫东 梁羽铁 刘春秀 刘怀民 刘颖 刘勇 罗涛 吕绮雯 马秋梅 马想 冒亚军 毛泽普 莫晓虎 宁飞鹏 平荣刚 邱进发 宋文博 孙胜森 孙晓东 孙永昭 田浩来 王纪科 王亮亮 文硕频 伍灵慧 吴智 谢宇广 言杰 严亮 姚剑 苑长征 袁野 张长春 张建勇 张雷 张学尧 张瑶 郑阳恒 朱永生 邹佳恒 

机构地区：[1]Department of Modern Physics,University of Science and Technology of China [2]Institute of High Energy Physics,CAS [3]Graduate University of Chinese Academy of Sciences [4]Nanjing University [5]Tsinghua University [6]Henan Normal University [7]Nanjing Normal University [8]Shandong University [9]Peking University [10]Guangxi University [11]Shanxi University [12]Zhengzhou University

出　　处：《Chinese Physics C》2009年第6期428-435,共8页中国物理C（英文版）

基　　金：Supported by CAS Knowledge Innovation Project (112901160333,111087513811);National Natural Science Foundation of China (10491300,10491303);100 Talents Program of CAS (U-25 and U-54)

摘　　要：This paper focuses mainly on the vertex reconstruction of resonance particles with a relatively long lifetime such as Ks^0, A, as well as on lifetime measurements using a 3-dimensional fit. The kinematic constraints between the production and decay vertices and the decay vertex fitting algorithm based on the least squares method are both presented. Reconstruction efficiencies including experimental resolutions are discussed. The results and systematic errors are calculated based on a Monte Carlo simulation.This paper focuses mainly on the vertex reconstruction of resonance particles with a relatively long lifetime such as Ks^0, A, as well as on lifetime measurements using a 3-dimensional fit. The kinematic constraints between the production and decay vertices and the decay vertex fitting algorithm based on the least squares method are both presented. Reconstruction efficiencies including experimental resolutions are discussed. The results and systematic errors are calculated based on a Monte Carlo simulation.

关 键 词：decay vertex resolution of decay length LIFETIME reconstruction efficiency 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]