Quasi-monoenergetic Laser-Plasma Positron Accelerator using Particle-Shower Plasma-Wave interactions

TL;DR

This paper proposes a novel, compact laser-plasma method to produce quasi-monoenergetic, ultra-relativistic positron beams using particle-shower plasma-wave interactions, potentially replacing large-scale accelerators.

Contribution

It introduces a new principle for trapping and accelerating divergent positrons from electromagnetic showers into monoenergetic beams using laser-driven plasma waves.

Findings

Simulations show acceleration of hundreds of MeV positron bunches.

The method achieves tunable, quasi-monoenergetic positron beams.

Existing lasers are sufficient for practical implementation.

Abstract

An all-optical centimeter-scale laser-plasma positron accelerator is modeled to produce quasi-monoenergetic beams with tunable ultra-relativistic energies. A new principle elucidated here describes the trapping of divergent positrons that are part of a laser-driven electromagnetic shower with a large energy spread and their acceleration into a quasi-monoenergetic positron beam in a laser-driven plasma wave. Proof of this principle using analysis and Particle-In-Cell simulations demonstrates that, under limits defined here, existing lasers can accelerate hundreds of MeV pC quasi-monoenergetic positron bunches. By providing an affordable alternative to kilometer-scale radio-frequency accelerators, this compact positron accelerator opens up new avenues of research.