1SLAC National Accelerator Laboratory, Menlo Park, CA 94720 USA
2ELI Beamlines, Institute of Physics of the Czech Academy of Sciences, Na Slovance 2, Prague, 18221 Czech Republic
3Thayer School of Engineering, Dartmouth College, 14 Engineering Dr, Hanover, NH 03755 USA
4Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 1H9 Canada
5Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
6European X-Ray Free-Electron Laser Facility GmbH, Schenefeld, 22869 Germany
7Deutsches Elektronen-Synchrotron, DESY, Notkestraße 85, Hamburg, D-22607 Germany
© The Author(s) 2019
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