The Swiss Light Source and SwissFEL at the Paul Scherrer Institute Frithjof Nolting, Christoph Bostedt, Thomas Schietinger and Hans Braun Eur. Phys. J. Plus, 138 2 (2023) 126 Published online: 06 February 2023 DOI: 10.1140/epjp/s13360-023-03721-y