中文摘要：

用数值方法研究了相干同步辐射（CSR）引发的微束团不稳定性．当电子通过北京X射线自由电子激光实验装置（BTF）的第二个磁压缩段时，CSR调制将使微束团失稳．这一不稳定性敏感的依赖于微束团twiss参数计算了不稳定的参数区．

英文摘要：

We numerically studied the microbunch instability driven by Coherent synchrotron radiation （CSR） in a magnet bunch compressor. High-frequency density perturbation may be significantly amplified when an electron beam passes through the Beijing XFEL Test Facility （BTF） magnet bunch compressor Ⅱ. The dependence of CSR-driven microbunch instability on bunch twiss parameters is sensitive. Dangerous area of twiss parameters is Outlined.