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arXiv · 2001.07187

Numerical simulations of electron-cloud build up in circular accelerators in the presence of multimode-distribution beams

X. Cui·S. Gilardoni·M. Giovannozzi·G. Iadarola
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Abstract

Electron cloud effects have become one of the main performance limitations for circular particle accelerators operating with positively-charged beams. Among other machines worldwide, the CERN Super Proton Synchrotron (SPS), as well as the Large Hadron Collider (LHC) are affected by these phenomena. Intense efforts have been devoted in recent years to improve the understanding of electron cloud (EC) generation with the aim of finding efficient mitigation measures. In a different domain of accelerator physics, non-linear resonances in the transverse phase space have been proposed as novel means of manipulating charged particle beams. While the original goal was to perform multi-turn extraction from the CERN Proton Synchrotron (PS), several other applications have been proposed. In this paper, the study of EC generation in the presence of charged particle beams with multimode horizontal distribution is presented. Such a peculiar distribution can be generated by different approaches, one of which consists in splitting the initial Gaussian beam distribution by crossing a non-linear resonance. In this paper, the outcome of detailed numerical simulations is presented and discussed.

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X. Cui, S. Gilardoni, M. Giovannozzi, G. Iadarola. 2020-01-20. Numerical simulations of electron-cloud build up in circular accelerators in the presence of multimode-distribution beams. https://doi.org/10.1209/0295-5075/129/24003

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