1. Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
2. I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
3. The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany.
4. Department of Chemistry and PULSE Institute, Stanford University, Stanford, CA 94305, USA.
5. Department of Chemistry, University of Hamburg, Martin-Luther-King Platz 6, 20146 Hamburg, Germany.
6. Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK.
7. TIFR Centre for Interdisciplinary Sciences, 36/P, Gopanpally Village, Ranga Reddy District, Hyderabad 500107, India.
8. State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China.
9. SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA.
10. Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada.