1. Section for Environmental Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, Norway
2. Institute for Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria
3. Aix Marseille Université, CNRS, LCE, UMR 7376, 13331 Marseille, France
4. Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York YO10 5DD, U.K.
5. Atmospheric Science, Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg, Sweden
6. Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway