论文标题
多阶段压缩中基于八杆的当前喇叭效果和发射增长校正
Octupole based current horn suppresion in multi-stage bunch compression with emittance growth correction
论文作者
论文摘要
高亮度线性加速器通常会产生电子束，并在电流轮廓的头部和/或尾部峰值产生峰值。由于纵向空间中的非线性相关性和压缩机的较高阶光学，这些当前的角是在压缩后形成的。已经提出，可以通过在压缩机中心附近插入八极磁体来纠正这种高阶压缩。但是，该方案提供了相关的横向踢，从而导致预计散发体的增长。我们在这里提出了一种方法，将八极磁体插入两个顺序的压缩机。通过调整两个八尖杆之间的$π$ betatron阶段的前进，可以在第二个八振体中校正相关的横向踢，同时提供高阶压缩的剪裁调整。
High brightness linear accelerators typically produce electron beams with peaks in the head and/or tail of the current profile. These current horns are formed after bunch compression due to non-linear correlations in the longitudinal phase space and the higher order optics of the compressor. It has been suggested that this higher order compression can be corrected by inserting an octupole magnet near the center of a bunch compressor. However, this scheme provides a correlated transverse kick leading to growth of the projected emittance. We present here a method whereby octupole magnets are inserted into two sequential bunch compressors. By tuning a $π$ betatron phase advance between the two octupoles, the correlated transverse kick from the first octupole can be corrected by the second, while providing a cummulative adjustment of the higher order compression.
