1. School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA
2. NASA Astrobiology Institute, NASA Ames Research Center, Mountain View, CA, USA
3. J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Prague 8, Czech Republic
4. Department of Physics, Wellesley College, Wellesley, MA, USA
5. Planetary Science Institute, Tucson, AZ, USA
6. Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, France
7. Research School of Physics, The Australian National University, Canberra, Australia