Non-planar four-mirror optical cavity for high intensity gamma ray flux production by pulsed laser beam Compton scattering off GeV-electrons

TL;DR

This paper presents the design and implementation of a non-planar four-mirror optical cavity with high finesse for high flux polarized gamma-ray production via Compton scattering, addressing key engineering challenges in an accelerator environment.

Contribution

It introduces a novel high-finesse non-planar cavity design with active stabilization using FPGA, suitable for high-intensity gamma-ray generation in particle accelerators.

Findings

Successfully operated the cavity at a particle accelerator.

Implemented a double feedback loop for active stabilization.

Addressed mechanical and tunability challenges in the cavity design.

Abstract

As part of the R&D toward the production of high flux of polarised Gamma-rays we have designed and built a non-planar four-mirror optical cavity with a high finesse and operated it at a particle accelerator. We report on the main challenges of such cavity, such as the design of a suitable laser based on fiber technology, the mechanical difficulties of having a high tunability and a high mechanical stability in an accelerator environment and the active stabilization of such cavity by implementing a double feedback loop in a FPGA.