Experimental capabilities for liquid jet samples at sub-MHz rates at the FXE Instrument at European XFEL

F. A. Lima, F. Otte, M. Vakili, F. Ardana-Lamas, M. Biednov, F. Dall'Antonia, P. Frankenberger, W. Gawelda, L. Gelisio, Huijong Han, X. Huang, Y. Jiang, M. Kloos, T. Kluyver, M. Knoll, K. Kubicek, Bermudez I.J. Macias, J. Schulz, O. Turkot, Y. Uemura, J. Valerio, H. Wang, H. Yousef, P. Zalden, D. Khakhulin, C. Bressler, and C. Milne

[BibTeX][pdf]doi:10.1107/S1600577523008159

The Femtosecond X-ray Experiments (FXE) instrument at the European X-ray Free-Electron Laser (EuXFEL) provides an optimized platform for investigations of ultrafast physical, chemical and biological processes. It operates in the energy range 4.7–20 keV accommodating flexible and versatile environments for a wide range of samples using diverse ultrafast X-ray spectroscopic, scattering and diffraction techniques. FXE is particularly suitable for experiments taking advantage of the sub-MHz repetition rates provided by the EuXFEL. In this paper a dedicated setup for studies on ultrafast biological and chemical dynamics in solution phase at sub-MHz rates at FXE is presented. Particular emphasis on the different liquid jet sample delivery options and their performance is given. Our portfolio of high-speed jets compatible with sub-MHz experiments includes cylindrical jets, gas dynamic virtual nozzles and flat jets. The capability to perform multi-color X-ray emission spectroscopy (XES) experiments is illustrated by a set of measurements using the dispersive X-ray spectrometer in von Hamos geometry. Static XES data collected using a multi-crystal scanning Johann-type spectrometer are also presented. A few examples of experimental results on ultrafast time-resolved X-ray emission spectroscopy and wide-angle X-ray scattering at sub-MHz pulse repetition rates are given.

Tags: European XFEL, liquid jet, sample delivery