All-optical Compton photon source generation via modulating pulse profile by convex focusing plasma mirror

TL;DR

This paper introduces a novel convex plasma mirror to enhance all-optical Compton photon sources by improving laser reflection efficiency and photon beam collimation, advancing gamma-ray generation techniques.

Contribution

The study proposes using a convex plasma mirror to simultaneously increase laser utilization and improve photon beam collimation in all-optical Compton scattering.

Findings

Convex plasma mirror enhances reflected laser length and focusing.

Improved photon beam collimation due to smaller transverse wave vector.

Higher laser utilization efficiency in gamma-ray generation.

Abstract

A relatively efficient scheme to generate energetic $\gamma$-ray is all-optical Compton scattering based on wakefield acceleration and plasma mirror where planar or concave solid target is usually employed to reflect driving pulse. For flat plasma mirror case, the colliding pulse radius is far larger than the radius of accelerated electron beam, which leads to smaller laser utilization efficiency. The concave plasma mirror can efficiently focus reflected laser to match electron beam radius. But the produced photon beam collimation is worse due to intensive transverse field and larger transverse wave vector of colliding laser. Here, we propose a new mechanism to achieve Compton scattering via employing convex plasma mirror. The convex plasma mirror improves reflected laser longitudinal length in addition to focusing effect, which ensures longer colliding time and larger laser utilization efficiency. Importantly, it leads transverse wave vector of colliding laser to be smaller, which guarantees better photon bunch collimation.