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arXiv · 2608.30455

Magnetizing nonlinear plasma wakefields for positron acceleration

Yung-Kun Liu·Pisin Chen·Ching-En Lin·Spencer Gessner·Bernhard Hidding
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Abstract

It is known that only a narrow plasma wakefield sliver in the electron-beam-driven blowout regime suits positron acceleration. Using 3D simulations, we show that matching the cyclotron frequency $\omega_{c}$ with the plasma frequency $\omega_{p}$ forms a stable electron column on axis, expanding the suitable phase space for positron acceleration sizably. For a plasma density $n_p = 10^{16}\text{ cm}^{-3}$ in a 35 T field, the interval expands 4.3 times, and a witness positron beam gains 100--150 MeV over 6 cm ($1.6$--$2.5$~GeV/m) with a 92\% capture rate.

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Yung-Kun Liu, Pisin Chen, Ching-En Lin, Spencer Gessner, Bernhard Hidding. 2026-08-31. Magnetizing nonlinear plasma wakefields for positron acceleration. https://arxiv.org/abs/2608.30455

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