Carl Caleman^1,8, Sebastian Cardoch⁸, Lucas M. Cornetta¹⁰, Alberto De Fanis², Emiliano De Santis^11,8, Simon Dold², Gilles Doumy⁷, Ulrich Eichmann¹², Xiaochun Gong¹³, Johan Gråsjö^14,8, Alice E. Green^15,16,2, Iyas Ismail¹⁷, Ludvig Kjellsson¹⁸, Eva Lindroth¹⁹, Tommaso Mazza², Jacobo Montaño², Terry Mullins¹, Christian Ott²⁰, Yevheniy Ovcharenko², Thomas Pfeifer²⁰, Maria Novella Piancastelli¹⁷, Ralph Püttner²¹, Nils Rennhack², Nina Rohringer^1,5, Cecilia Sánchez-Hanke²², Conny Såthe¹⁸, Philipp Schmidt², Björn Senfftleben², Marc Simon¹⁷, Nicuşor Tîmneanu⁸, Moto Togawa², Kiyoshi Ueda^23,24, Sergey Usenko², Hans Jakob Wörner²⁵, Weiqing Xu^26,27, Zhong Yin²⁸, Linda Young^6,7, Joseph Nordgren⁸, Marcus Agåker^18,8, Johan Söderström⁸, Sonia Coriani³, Michael Meyer², Robin Santra^1,5, and Jan-Erik Rubensson^8,§

• ¹Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
• ²European XFEL, Schenefeld, Germany
• ³Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
• ⁴Department of Chemistry, Norwegian University of Science and Technology, Trondheim, Norway
• ⁵Department of Physics, University of Hamburg, Hamburg, Germany
• ⁶Department of Physics, The University of Chicago, Chicago, Illinois, USA
• ⁷Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois, USA
• ⁸Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
• ⁹Synchrotron SOLEIL, Gif-sur-Yvette Cedex, France
• ¹⁰Instituto de Física da Universidade de São Paulo, São Paulo, Brazil
• ¹¹Department of Physics, University of Rome Tor Vergata and INFN, Roma, Italy
• ¹²Max-Born-Institut, Berlin, Germany
• ¹³State Key Laboratory of Extreme Photonics and Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, China
• ¹⁴Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
• ¹⁵Stanford PULSE Institute, Menlo Park, California, USA
• ¹⁶EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, United Kingdom
• ¹⁷Laboratoire de Chimie Physique – Matière et Rayonnement, CNRS, Sorbonne Université, Paris, France
• ¹⁸MAX IV Laboratory, Lund University, Lund, Sweden
• ¹⁹Department of Physics, Stockholm University, Stockholm, Sweden
• ²⁰Max-Planck-Institut für Kernphysik, Heidelberg, Germany
• ²¹Fachbereich Physik, Freie Universität Berlin, Berlin, Germany
• ²²Diamond Light Source, Didcot, United Kingdom
• ²³Department of Chemistry, Tohoku University, Sendai, Japan
• ²⁴School Physical Science and Technology, ShanghaiTech University, Shanghai, China
• ²⁵Laboratory of Physical Chemistry, ETH Zürich, Zurich, Switzerland
• ²⁶Center for Transformative Science, ShanghaiTech University, Shanghai, China
• ²⁷Shanghai HIgh repetitioN rate XFEL and Extreme light facility (SHINE), ShanghaiTech University, Shanghai, China
• ²⁸International Center for Synchrotron Radiation Innovation Smart, Tohoku University, Sendai, Japan

• ^*These authors contributed equally to this work.
• ^†Contact author: sangkil.son@cfel.de
• ^‡Contact author: thomas.baumann@xfel.eu
• ^§Contact author: jan-erik.rubensson@physics.uu.se