Spectrum of multi-bunch beam position model and parameter acquisition algorithm

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.