交变极性聚焦及其效应模拟

利用交变极性聚焦磁场聚焦存在稳定解的条件，合理设置聚焦布局，可有效抑止束质心的Corkscrew运动。实验结果表明，采用交变极性聚焦场聚焦，抑制了束脉冲顶部质心横向运动的发展，同时可剔除束脉冲前后沿能散度较大的那部分束。对实验所获束质心运动结果进行了打靶效应模拟，采用交变极性聚焦场聚焦，抑制束质心横向运动的效果是显著的。

Focus and Focusing Effect Simulation in an Alternate Solenoid Field

A reasonable focusing system is set up using the precondition transporting stably intense beams in an alternate focusing solenoid field and the focusing system can confine Corkscrew oscillations. The experimental results show that the increase of the centroid transverse displacement in the beam-pulse flattop duration is confined and the bigger energy-sweep beams are partially rejected in the alternate focusing solenoid field. The results of focusing effect simulation also show that the alternate focusing solenoid field obviously confines corkscrew oscillations.