Author Affiliations

Chuan Cheng,¹ Leszek J. Frasinski,² Gönenç Moğol,¹ Felix Allum,^3,4,5 Andrew J. Howard,⁴ Philip H. Bucksbaum,^4,5 Mark Brouard,³ Ruaridh Forbes,^4,5 and Thomas Weinacht¹

¹Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800, USA

²Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, United Kingdom

³Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom

⁴Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA

⁵Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA