以储存环逐圈位置频谱模型为基础, 通过一些假设条件推导出多束团模式下束流位置的频谱模型。利用上海光源储存环受激多束团位置信号频谱数据, 使用遗传算法进行多曲线数据拟合得到模型参数。结果表明: 在迭代100次的条件下, 该模型与原数据所有曲线的相关性均在95%以上, 并且可以精确估计多束团频谱曲线的双峰分裂。曲线拟合后的参数可以监测储存环阻抗的变化。

Based on the spectrum of turn-by-turn model for the storage ring, spectrum of multi-bunch beam position model was derived through some assumptions. Spectrum of excited electron beam position was analyzed at Shanghai Synchrotron Radiation Facility(SSRF) and Genetic Algorithm was used to fit multi-curve data and the model parameters were obtained. The results show that, after 100 times iteration, all the correlation of fitted data and original data can be up to 95%, and the model can accurately estimate a bimodal split of the spectrum curve. The parameters can be used for monitoring the impedance of the storage ring.