Brilliant circularly polarized $\gamma$-ray sources via single-shot laser plasma interaction

TL;DR

This paper demonstrates a novel method to generate brilliant circularly polarized gamma-ray beams using laser plasma interactions, achieving significant polarization and brilliance suitable for advanced scientific applications.

Contribution

It introduces a new approach combining laser wakefield acceleration and plasma mirror techniques to produce highly polarized gamma-ray sources with high brilliance.

Findings

Achieved about 37% polarization degree at 1 MeV.

Generated gamma-ray brilliance exceeding 10^21 photons/(s·mm^2·mrad^2·0.1% BW).

Method is robust and feasible with current laser and plasma technology.

Abstract

Circularly polarized (CP) $\gamma$-ray sources are versatile for broad applications in nuclear physics, high-energy physics and astrophysics. The laser-plasma based particle accelerators provide accessibility for much higher flux $\gamma$-ray sources than conventional approaches, in which, however, the circular polarization properties of emitted $\gamma$-photons are used to be neglected. In this letter, we show that brilliant CP $\gamma$-ray beams can be generated via the combination of laser plasma wakefield acceleration and plasma mirror techniques. In weakly nonlinear Compton scattering scheme with moderate laser intensities, the helicity of the driving laser can be transferred to the emitted $\gamma$-photons, and their average polarization degree can reach about $\sim 37\%$ ($21\%$) with a peak brilliance of $\gtrsim 10^{21}~$photons/(s $\cdot$ mm$^2 \cdot$ mrad$^2 \cdot$ 0.1% BW) around 1~MeV (100~MeV). Moreover, our proposed method is easily feasible and robust with respect to the laser and plasma parameters.