Robustness of a plasma acceleration based Free Electron Laser

TL;DR

This paper investigates the robustness of chromatic matching in plasma accelerator-based Free Electron Lasers, analyzing sensitivity to source jitters and equipment imperfections to improve beam quality for FEL applications.

Contribution

It provides a detailed analysis of the robustness of chromatic matching strategies for FELs driven by plasma accelerators, considering various realistic errors and jitters.

Findings

Chromatic matching shows resilience to certain jitters and misalignments.

Sensitivity analysis identifies critical parameters affecting FEL performance.

Results suggest potential for stable FEL operation with plasma-accelerated beams.

Abstract

Laser Plasma Accelerators (LPA) can sustain GeV/m accelerating fields offering outstanding new possibilities for compact applications. Despite the impressive recent developments, the LPA beam quality is still significantly lower than in the conventional radio-frequency accelerators, which is an issue in the cases of demanding applications such as Free Electron Lasers (FELs). If the electron beam duration is below few tens of femtosecond keeping pC charges, the mrad level divergence and few percent energy spread are particularly limiting. Several concepts of transfer line were proposed to mitigate those intrinsic properties targetting undulator radiation applications. We study here the robustness of the chromatic matching strategy for FEL amplification at 200~nm in a dedicated transport line, and analyze its sensitivity to several parameters. We consider not only the possible LPA source jitters, but also various realistic defaults of the equipment such as magnetic elements misalignements or focussing strength errors, unperfect undulator fields, etc...