RF regulation with superconducting cavities and beam operation using a frequency shifted cavity

TL;DR

This paper proposes a novel regulation method using a frequency shifted superconducting cavity to control electron bunch energy in free-electron lasers, aiming for rapid switching and potential continuous operation upgrades.

Contribution

It introduces a new approach to modulate electron bunch energy using a frequency shifted cavity, addressing switching speed limitations in superconducting FELs.

Findings

Demonstrates feasibility of frequency shifted cavity for bunch energy regulation

Achieves microsecond-level switching times in beam operation

Provides a pathway for CW upgrade of EuXFEL

Abstract

The free-electron laser FLASH at DESY and the European XFEL are operated with superconducting radio frequency cavities and supply beam to several user experiments. The switching time between experiments is limited to dozens of microseconds. This contribution will show a regulation with a frequency shifted superconducting cavity to manipulate and change the accelerating properties of electron bunches with 250 kHz.The main challenge of the concept presented in this contribution can be summarized in this statement: finding a way to modulate the energy of individual bunches in a single-source multiple-cavity scheme for a potential CW upgrade of the EuXFEL.