# Low power commissioning of an innovative laser beam circulator for inverse Compton scattering Gamma-ray source

## TL;DR

This paper details the optical commissioning of a high-power laser beam circulator designed for gamma-ray production via inverse Compton scattering, demonstrating significant power enhancement without electron beam involvement.

## Contribution

It introduces a novel laser beam circulator with alignment and synchronization methods that significantly increase laser power at the interaction point.

## Key findings

- Laser beam power at the IP increased by over 25 times.
- Potential to achieve over 1 kW average laser power at the IP.
- Successful low-power tests validating optical performance and alignment methods.

## Abstract

We report on the optical commissioning of the high power laser beam circulator (LBC) for the high brightness Compton {\gamma}-ray source Extreme Light Infrastructure for Nuclear Physics. Tests aiming at demonstrating the optical performances of the LBC have been realized with a low-power pulsed laser-beam system and without electron beam. We show that, with the developed alignment and synchronization methods coming from the LBC design study presented in the Dupraz et al. paper [1], the LBC enhances the laser-beam power available at the interaction point (IP) by a factor in excess of 25. This corresponds to a potential of bringing the average laser-beam power in excess of 1 kW when the LBC is injected with the interaction point laser-beam pulse energy of 400 mJ at 100 Hz.