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arXiv · 1504.06233

The Side-Effects of the Space Charge Field Introduced by Hollow Electron Beam in the Electron Cooler of CSRm

Mei-Tang Tang·Xiao-Dong Yang·Li-Jun Mao·Jie Li·Xiao-Ming Ma·Tai-Lai Yan·Wen-Heng Zheng·He Zhao·Bo Wu·Geng Wang·Shuang Ruan·Xiao-Ping Sha
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Abstract

Electron cooler is used to improve the quality of the beam in synchrotron, however it also introduces nonlinear electromagnetic field, which cause tuneshift, tunespread and may drive resonances leading to beam loss. In this paper the tuneshift and the tunespread caused by nonlinear electromagnetic field of the hollow electron beam was investigated, and the resonance driving terms of the nonlinear electromagnetic field was analysed. The differences were presented comparing with the solid electron beam. The calculations were performed for $^{238}U^{32+}$ ions of energy 1.272MeV stored in CSRm, using the parameters given in table1. The conclusion is that in this situation nonlinear field caused by the hollow electron beam do not lead to serious resonances.

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Mei-Tang Tang, Xiao-Dong Yang, Li-Jun Mao, Jie Li, Xiao-Ming Ma, Tai-Lai Yan, Wen-Heng Zheng, He Zhao, Bo Wu, Geng Wang, Shuang Ruan, Xiao-Ping Sha. 2015-04-23. The Side-Effects of the Space Charge Field Introduced by Hollow Electron Beam in the Electron Cooler of CSRm. https://doi.org/10.1088/1674-1137/39/12/127003

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