摘要
同步辐射光源及自由电子激光装置需要一种新型的束流损失探测系统,用于实时监测小间隙插入件处的束流损失。为此研制了采用光纤作为探测器的束流损失监测系统,系统包含长30 m的阶跃光纤、光电倍增管、8 GS/s高速采集板卡(10 bits)及配套作为输入输出控制器的PXI总线工控机。数据采集处理软件在Linux系统下基于EPICS框架开发。为使系统能在多束团填充的储存环上应用,设计了一种双端测量方案及数据处理方法。初步束流实验结果表明,该系统可在低至1 mA条件下监测到束损信号,光脉冲计数率可用于表征束流损失剂量,储存环220 mA恒流供光模式下本底噪声约占总计数率的3.56%。
Background： A new type of beam loss monitor （BLM） system is needed in the synchrotron radiation light source or FEL facility to monitor the real-time beam loss inside the small-gap insertion devices. Purpose： A BLM system was developed with optical fiber as the probe to meet the requirements of SSRF. Methods： The whole system consists of a 30-m long step-index fiber, photomultiplier tubes （PMT）, a 10-bit 8-GS/s high-speed waveform digitizer and a PXI input-output controller. The software was developed under the Linux system based on Experimental Physics and Industrial Control System （EPICS）. A new measurement and corresponding calculation method were designed to make the system work well with the multi-bunch operation mode in the storage ring of SSRF. Results： The BLM system worked well at SSRF. And the results of beam experiments showed that the system could detect beam loss properly even at the 1-mA low current case. Conclusions： This system could be used in the detection of beam loss dose and position. In the experiments the counts of light pulses can be used as a rough estimation of beam loss dose. The noise floor is about 3.56% of the total count in the 220-mA top-up user operation mode.
出处
《核技术》
CAS
CSCD
北大核心
2013年第8期8-14,共7页
Nuclear Techniques
