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arXiv · 2610.07322

Limits on energy recovery for positron acceleration in a warm plasma column

Max Varverakis·Spencer Gessner·Severin Diederichs·Carl A. Lindstrøm
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Abstract

Beam-driven plasma wakefield acceleration (PWFA) is a promising candidate for realizing a future linear collider, owing to the extremely high field gradients that are produced in plasmas. Despite recent success in high-gradient and high-efficiency electron PWFA, efficient positron PWFA remains a challenge. The warm plasma column regime offers stable, high-quality acceleration of positron beams in a plasma electron filament, albeit at low energy-transfer efficiencies. We explore the possibility of employing an electron energy recovery beam to extract residual energy from the plasma wakefield and increase the efficiency of this scheme. Our particle-in-cell simulations reveal that certain mechanisms, including higher-order ionization and ion motion, limit our ability to further extract energy from the plasma wakefield.

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Max Varverakis, Spencer Gessner, Severin Diederichs, Carl A. Lindstrøm. 2026-10-05. Limits on energy recovery for positron acceleration in a warm plasma column. https://arxiv.org/abs/2610.07322

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