BPM技术用于环形电子束位置测量的可行性分析

The Analysis of Feasibility on the Usage of BPM System for Position Measurement of Annular Beams

为了对传输管道半径24mm,电子束半径19mm,厚度3mm的环形电子束位置开展非阻拦测量,选择了BPM技术方案。对比研究了真空管道中环形电子束与位于束团中心的实心束在管道壁上产生的场分布,证明BPM测量技术可以用于电流密度均匀分布的环形电子束。采用点密度不均匀性模型,分析了环形电子束角向不均匀性对测量精度的影响。结果显示,当环形电子束电流密度不均匀性应为10%时,对位置分辨率精度的影响为0.1mm。

For non-interceptive position measurement of annular beams with travelling radius of 24 mm, beam radius of 19 mm, thickness of 3mm,the BPM technical scheme was chosen. The electric field on the wall of a circular chamber produced by an annular beam is compared with that of a pencil beam located at the same axes. It is proved that BPM system can be used for position measurement of annular beams. Taken a single-point non-uniform model, the influence of the azimuthally non-uniformity on measurement accuracy is analyzed. And it is revealed that 10% single-point non-uniformity caused a 0.1mm measurement deviation.