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arXiv · 2303.18114

Positron acceleration in plasma waves driven by non-neutral fireball beams

Thales Silva·Jorge Vieira
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Abstract

Plasma-based positron acceleration is still an open question, as the most efficient regimes for electron acceleration (quasi-linear and blowout) are not directly applicable to positrons. Nevertheless, positron acceleration is a stepping stone on the path toward a plasma-based lepton collider. In this work, we propose a scheme for positron acceleration based on the spatial overlap of a driver (electron or laser) beam and a positron beam, also known as a fireball beam. Under appropriate conditions, these beams can self-consistently evolve toward a hollow driver and focused positron beam on-axis, driving plasma waves suitable for positron acceleration. This evolution seems to be a manifestation of the current filamentation instability. We discuss how the self-consistent dynamics affect the beam quality and perform a preliminary tolerance study.

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Thales Silva, Jorge Vieira. 2023-03-31. Positron acceleration in plasma waves driven by non-neutral fireball beams. https://doi.org/10.1103/physrevaccelbeams.26.091301

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