基于积分束流变压器的加速器束团电荷量测量系统

Bunch charge monitoring system based on integrating current transformer

为满足清华大学加速器实验室光阴极微波电子枪实验平台的发展需求,设计了束团电荷量测量系统,可以实现实时测量加速器束团电荷量的目标。这套测量系统基于积分束流变压器,包括前置放大器、门控积分器、模数转换和数据传输模块。利用信号发生器模拟束流,对整套系统进行了离线测量实验。当前置放大器放大倍数取200和20时,AD转换值和束流电荷的比值分别为2.181 PC-1和0.195 PC-1,与理论值2.070 PC-1和0.207 PC-1基本吻合;其对应的电荷量测量误差分别小于2 PC和15 PC。测量结果和模拟束流电荷量值的拟合曲线线性度好,相关系数的平方均大于0.999 0。该结果验证了系统的可行性。

A bunch charge monitor system has been designed for the photocathode RF gun of Accelerator Laboratory, Tsinghua University. Integrating current transformer is the most important part of the system, and parts of the system after integrating current transformer consist of a preamplifier, an integrator, an AD converter and a data collection module. The system does not destroy the beam, and it can monitor the bunch charge in the high-radiation environment around accelerator. The results of some off-line tests show that the system is feasible.