Open AccessX‐ray photon diagnostics at the European XFEL
Author(s) -
Grünert Jan,
Carbonell Marc Planas,
Dietrich Florian,
Falk Torben,
Freund Wolfgang,
Koch Andreas,
Kujala Naresh,
Laksman Joakim,
Liu Jia,
Maltezopoulos Theophilos,
Tiedtke Kai,
Jastrow Ulf Fini,
Sorokin Andrey,
Syresin Evgeny,
Grebentsov Alexander,
Brovko Oleg
Publication year - 2019
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577519006611
Subject(s) - undulator , beamline , optics , physics , free electron laser , laser , photon energy , beam (structure) , photon , lasing threshold , cathode ray , electron , nuclear physics
The European X‐ray Free‐Electron Laser (European XFEL) (Altarelli et al. , 2006; Tschentscher et al. , 2017), the world's largest and brightest X‐ray free‐electron laser (Saldin et al. , 1999; Pellegrini et al. , 2016), went into operation in 2017. This article describes the as‐built realization of photon diagnostics for this facility, the diagnostics commissioning and their application for commissioning of the facility, and results from the first year of operation, focusing on the SASE1 beamline, which was the first to be commissioned. The commissioning consisted of pre‐beam checkout, first light from the bending magnets, X‐rays from single undulator segments, SASE tuning with many undulator segments, first lasing, optics alignment for FEL beam transport through the tunnel up to the experiment hutches, and finally beam delivery to first users. The beam properties assessed by photon diagnostics throughout these phases included per‐pulse intensity, beam position, shape, lateral dimensions and spectral properties. During this time period, the machine provided users with up to 14 keV photon energy, 1.5 mJ pulse energy, 300 FEL pulses per train and 4.5 MHz intra‐bunch train repetition rate at a 10 Hz train repetition rate. Finally, an outlook is given into the diagnostic prospects for the future.