Bright \AA ngstrom and Picometre Free Electron Laser Based on the LHeC Energy Recovery Linac

TL;DR

This paper explores the potential of the LHeC energy recovery linac to generate high-brilliance X-ray and photon pulses at Angstrom and picometre wavelengths using a free electron laser, surpassing current FEL capabilities.

Contribution

It presents a novel concept of using the LHeC ERL to produce ultra-bright X-ray and photon pulses at unprecedented short wavelengths, including the picometre regime.

Findings

Potential to produce orders of magnitude higher brilliance at Angstrom wavelengths.

Feasibility of generating photon pulses down to a few picometres.

Demonstration of the LHeC-based FEL's capability for ultra-short wavelength radiation.

Abstract

The Large Hadron electron Collider (LHeC) is a proposed future particle-physics project colliding 60 GeV electrons from a six-pass recirculating energy-recovery Linac (ERL) with 7 TeV protons stored in the LHC. The ERL technology allows for much higher beam current and, therefore, higher luminosity than a traditional Linac. The high-current, high-energy electron beam can also be used to drive a free electron laser (FEL). In this study, we investigate the performance of an LHeC-based FEL, operated in the self-amplified spontaneous emission mode using electron beams after one or two turns, with beam energies of, e.g., 10, 20, 30 and 40 GeV, and aim at producing X-ray pulses at wavelengths ranging from 8~\AA\ to 0.5~\AA . In addition, we explore a possible path to use the 40 GeV electron beam for generating photon pulses at much lower wavelengths, down to a few picometre. We demonstrate that such ERL-based high-energy FEL would have the potential to provide orders of magnitude higher average brilliance at \AA\ wavelengths than any other FEL either existing or proposed. It might also allow a pioneering step into the picometre wavelength regime.