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arXiv · 2007.07713

Proton beam self-modulation seeded by electron bunch in plasma with density ramp

K. V. Lotov·V. A. Minakov
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Abstract

Seeded self-modulation in a plasma can transform a long proton beam into a train of micro-bunches that can excite a strong wakefield over long distances, but this needs the plasma to have a certain density profile with a short-scale ramp up. For the parameters of the AWAKE experiment at CERN, we numerically study which density profiles are optimal if the self-modulation is seeded by a short electron bunch. With the optimal profiles, it is possible to "freeze" the wakefield at approximately half the wavebreaking level. High-energy electron bunches (160 MeV) are less efficient seeds than low-energy ones (18 MeV), because the wakefield of the former lasts longer than necessary for efficient seeding.

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BibTeXRIS

K. V. Lotov, V. A. Minakov. 2020-07-15. Proton beam self-modulation seeded by electron bunch in plasma with density ramp. https://doi.org/10.1088/1361-6587/abba42

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