Cavity based x-ray free electron laser demonstrator at the European X-ray Free Electron Laser facility

In this article, the concept of a recently funded R project for installation proof-of-concept cavity-based x-ray free electron laser (CBXFEL) demonstrator experiment at European XFEL facility is presented, with first results expected in 2024. It composed an cavity design backscattering geometry 133 m round trip length using cryogenically cooled diamond crystals. employs retroreflection to reduce sensitivity vibrations. The FEL radiation produced four undulator segments 20 total length. Simulations 16 GeV beam energy and 250 pC bunch charge show that pulses saturation surpass state-of-the-art sources considering spectral flux three-dimensional coherence. However, stability proof setup severely challenged by finite thermal transport Therefore, suitable measures such as cooling crystals 70 K are explained paper additional ones will have be developed course project.