实验比较了高计数率下三种光电倍增管电压供给方式的增益变化和温度效应。在不同的光电倍增管工作电压下,分别对阳极输出和打拿极输出方式的增益计数率性能作了检验。讨论了高计数率下引起增益变化的三种因素:极间电压分配的变化,“充电”和“疲劳”效应。采用晶体管发射极跟随器供压方式,较低的光电倍增管工作电压和打拿极输出方式可以减小闪烁体-光电倍增管系统增益的计数率效应,提高稳定度。 The experiment compares the gain variation and temperature effect of the three photomultiplier tube voltage supply modes under high count rate. At different photomultiplier tube operating voltage, respectively, the anode output and dynode output gain count rate performance has been tested. Three factors that cause gain changes at high count rates are discussed: changes in voltage distribution across poles, “charge” and “fatigue” effects. The transistor emitter follower supply method, lower PMT operating voltage and dynode output mode can reduce the scintillator - PMT system gain count rate effect and improve the stability.