束流轨道与相关环境参数的同步诊断技术

粒子加速器由于受地基振动、环境温度、热效应等因素的影响,导致束流位置探头(BPM)所在真空盒的机械中心相对四极铁磁中心的漂移较大,因此很难提高束流轨道的绝对测量精度。探索利用电容式探头实时检测该漂移量的方法。首先分析了电容式探头的测量原理,并设计了轨道振动同步诊断方案,然后设计了专用探头,并利用数据采集设备对探头的线性度、精度和频率响应进行实验室测试。结果显示电容式探头能检测到2μm的相对位移,且可有效检测300Hz以下的振动频率,可用于束流轨道与相关环境参数的同步诊断。

Synchronous measurement of beam orbit and relative environment parameters

The mechanical center of beam position monitor (BPM) vacuum tune in particle accelerator can be drifted comparatively large away from the magnetic center of quadrupole under the environment of foundation vibration, temperature, thermal effects, etc. We tried to apply capacitor sensor to real-time drift monitoring. Firstly, we analyzed the capacitor’s measurement principle, and designed the scheme of synchronous measurement of beam orbit vibration. After that, we made a dedicated test capacitor sensor, and tested the sensor’s linearity, resolution and frequency response with data acquisition instruments in laboratory. Results show that it can monitor 2 μm relative movement and up to 300 Hz vibration frequency. Capacitor sensors can be applied to the synchronous measurement of beam orbit and relative environment parameters.