We present the development and laboratory testing of an alignment setup for the STERN experiment at the European XFEL, aimed at exploring beam-based THz radiation generation methods using Cherenkov waveguides. The setup employs an alignment laser to simulate the electron beam trajectory, enabling the accurate positioning of critical components, such as a copper block housing dielectric waveguides. The alignment process involves scintillator screens placed before and after the vacuum chamber to measure the electron beam trajectory, with the alignment laser subsequently adjusted to replicate this path. The experimental validation focused on the reproducibility of alignment under simulated operational conditions, testing the positioning and movement of mirrors, and ensuring the stability of the alignment system for the critical components.
Wernsmann et al. (Wed,) studied this question.