Empirical Optimization of Undulator Tapering at FLASH2 and Comparison with Numerical Simulations

TL;DR

This paper presents an empirical approach to optimize undulator tapering in the FLASH2 free-electron laser, demonstrating improved radiation power and comparing results with numerical simulations to validate the method.

Contribution

It introduces a multidimensional empirical optimization method for undulator tapering in FLASH2 and compares its effectiveness with numerical simulations.

Findings

Enhanced radiation power beyond saturation point

Empirical optimization aligns well with simulations

Improved laser efficiency through optimized taper profiles

Abstract

In a free-electron laser equipped with variable-gap undulator modules, the technique of undulator tapering opens up the possibility to increase the radiation power beyond the initial saturation point, thus enhancing the efficiency of the laser. The effectiveness of the enhancement relies on the proper optimization of the taper profile. In this work, a multidimensional optimization approach is implemented empirically in the x-ray free-electron laser FLASH2. The empirical results are compared with numerical simulations.