BESⅢ飞行时间电子学在线刻度电路  

Calibration circuit for TOF read-out electronics of BES Ⅲ

作　　者：封常青[1] 刘树彬[1] 黄亚齐[1] 安琪[1] 

机构地区：[1]中国科学技术大学近代物理系,中国科学院核探测技术与核电子学重点实验室,合肥230026

出　　处：《核技术》2010年第6期477-480,共4页Nuclear Techniques

基　　金：国家大科学工程北京正负电子对撞机升级项目(BEPCII-UDDETF-309-HT182/2004);国家自然科学基金(10405023)资助

摘　　要：本文介绍了BESIII(北京正负电子对撞机第三代谱仪)飞行时间(TOF)读出电子学在线刻度电路。该电路被集成在读出电子学插件上,用VME总线接口在线控制高精度DAC和高速模拟开关,产生幅度(电荷)可程控的指数衰减脉冲,对电子学通道进行时间测量检测和电荷测量的非线性校准,有大于20倍的电荷动态范围和好于10bit的精度,能有效实现电荷非线性的校准功能。经测试,刻度修正后TOF电子学电荷测量的积分非线性小于0.6%,远好于修正前2%的性能指标,满足设计要求,目前该刻度电路已成功应用于BESIII工程。A calibration circuit for BESIII TOF electronics is described in this paper. An exponential-decay calibrating signal, of which the charge （integrated area of amplitude） was set by remotely-controlled DAC via VME bus, was generated by fast analog switch and fed to each time-and-charge measurement channel of TOF readout electronics. It has the charge accuracy of better than 10 bits and the dynamic range of more than 20 times. Detailed tests suggest that the nonlinearity of charge measurement, normally about 2%, can be greatly reduced to less than 0.6% after calibration. This calibration circuit scheme has been applied in BESIII project successfully.

关 键 词：在线刻度 BESⅢ TOF电子学 

分 类 号：TL824[核科学技术—核技术及应用]