Decoupling acceleration and wiggling in a laser-produced Betatron source

TL;DR

This paper presents a novel laser-driven Betatron X-ray source that independently optimizes electron acceleration and X-ray emission by tailoring plasma density, resulting in brighter, more stable, and more collimated X-ray beams.

Contribution

It introduces a plasma density profile tailoring technique to decouple acceleration and wiggling, enhancing Betatron X-ray source performance.

Findings

Betatron photon energy controlled by plasma wiggler length

Independent optimization of acceleration and X-ray production demonstrated

Produced brighter, stable, and collimated X-ray beams

Abstract

Betatron radiation is produced in Laser Plasma Accelerators when the electrons are accelerated and simultaneously wiggle across the propagation axis. The mechanisms of electron acceleration and X-ray radiation production follow different scaling laws, and the brightest X-ray radiation is often produced for an electron beam with a lower quality in terms of energy and divergence. Here, we report a laser-driven Betatron X-ray source where the plasma density profile is tailored in order to separate the acceleration and wiggler stages, which allows for the independent optimizations of acceleration and X-ray production. We demonstrate this concept experimentally, and show that the Betatron photon energy can be controlled by adjusting the length of the plasma wiggler. This scheme offers a path to overcome the limitations of conventional Betatron sources, enabling the production of bright, stable, energetic, and collimated X-ray beams.