Study of MRPC technology for BESIII endcap-TOF upgrade  

作　　者：Xin Li Yongjie Sun Cheng Li Zhen Liu Yuekun Heng Ming Shao Xiaozhuang Wang Zhi Wu Ping Cao Mingming Chen Hongliang Dai Shubing Liu Xiaolan Luo Xiaoshan Jiang Shengsen Sun Zebo Tang Weijia Sun Siyu Wang Meihang Xu Rongxing Yang Kejun Zhu 

机构地区：[1]University of Science and Technology of China,Hefei 230026,China [2]Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China [3]State Key Laboratory of Particle Detection and Electronics(USTC-IHEP),Hefei,China

出　　处：《Radiation Detection Technology and Methods》2017年第2期31-36,共6页辐射探测技术与方法（英文）

基　　金：supported by the National Natural Science Foundation of China(Nos.10979003,11675172,U1232206);Chinese Academy of Sciences(No.1G201331231172010).

摘　　要：Purpose In order to improve the charged particle identi-fication capability,end-cap time-of-flight(ETOF)detector of the Beijing Spectrometer(BESIII)has been upgraded with multi-gap resistive plate chamber(MRPC)technology,aiming at an overall time resolution of 80 ps for minimum-ionization particles to extend the K/πseparation(2σ)momentum range to 1.4 GeV/c.Methods The previous version of ETOF in BESIII consisted of plastic scintillators.The multi-hit events distort both shape and amplitude of the output signals.MRPC technique was chosen for the BESIII ETOF upgrade as it provides high time resolution and high detection efficiency,is of relatively low cost and is insensitive to neutral particles.Most importantly,the fine segmentation of the MRPC readout stripes can suppress multi-hit events effectively.Results The final design of MRPC module for ETOF is characterized by double-stack(2×6)structure,dual-end readout mode and precision electronics.To batch-produce and test these MRPC modules,a series of tools and production procedures as well as related performance simulation and test methods were developed.Results showed that each MRPC module’s intrinsic time resolution(including the electronics contribution)is around 50 ps and the efficiency is better than 97%.The overall performance of the upgraded ETOF is better than the designed index.The new ETOF has been successfully installed at BESIII and run in 2016.

关 键 词：Multi-gap resistive plate chamber Endcap time-of-flight detector Particle identification Beijing spectrometer High time resolution 

分 类 号：O57[理学—粒子物理与原子核物理]