European XFEL, Holzkoppel 4, Schenefeld 22869, Germany.
Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, Hamburg 22603, Germany.
J Synchrotron Radiat. 2019 Sep 1;26(Pt 5):1422-1431. doi: 10.1107/S1600577519006611. Epub 2019 Aug 2.
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.
欧洲 X 射线自由电子激光（European XFEL）（Altarelli 等人，2006 年；Tschentscher 等人，2017 年）是世界上最大、最亮的 X 射线自由电子激光（Saldin 等人，1999 年；Pellegrini 等人，2016 年），于 2017 年投入运行。本文描述了该设施光子诊断的建成实现、诊断调试及其在设施调试中的应用，以及运行第一年的结果，重点介绍了首批调试的 SASE1 光束线。调试包括预束检查、来自弯曲磁铁的初始光束、单个波荡器段的 X 射线、使用许多波荡器段的 SASE 调谐、首次激光发射、通过隧道传输到实验舱的 FEL 光束的光学对准，以及最终将光束传输到第一批用户。在这些阶段，光子诊断评估的光束特性包括脉冲强度、光束位置、形状、横向尺寸和光谱特性。在此期间，该机器向用户提供了高达 14keV 的光子能量、1.5mJ 的脉冲能量、每个脉冲 300 个 FEL 脉冲和 4.5MHz 的内束团重复率，重复率为 10Hz。最后，展望了未来的诊断前景。
