1. Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, 00014 Helsinki, Finland.
2. Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
3. Department of Chemistry and Cooperative Institute for Research in the Environmental Sciences, University of Colorado Boulder, Boulder, CO 80309, USA.
4. Faculty of Physics, University of Vienna, 1090 Vienna, Austria.
5. Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, 33014 Tampere, Finland.
6. Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany.
7. Department of Applied Physics, University of Eastern Finland, 70211 Kuopio, Finland.
8. Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, CH-5232 Villigen, Switzerland.
9. CERN, the European Organization for Nuclear Research, CH-1211 Geneva 23, Switzerland.
10. Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
11. CENTRA and Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal.
12. Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany.
13. Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany.
14. Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China.
15. Jiangsu Provincial Collaborative Innovation Center of Climate Change, Nanjing 210023, China.
16. Helsinki Institute of Physics, University of Helsinki, 00014 Helsinki, Finland.
17. Institute of Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria.
18. Ionicon Analytik Ges.m.b.H., 6020 Innsbruck, Austria.
19. Institute of Physics, University of Tartu, 50411 Tartu, Estonia.
20. School of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea.
21. Aerodyne Research, Inc., Billerica, MA 01821, USA.
22. P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 119991 Moscow, Russia.
23. Finnish Meteorological Institute, 00560 Helsinki, Finland.
24. Department of Atmospheric and Oceanic Sciences, University of Colorado, Boulder, CO 80309, USA.
25. School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK.
26. Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, 28006 Madrid, Spain.
27. Institute of Chemistry, Eötvös University, H-1117 Budapest, Hungary.
28. Institute of Physics, Johannes Gutenberg University Mainz, 55128 Mainz, Germany.
29. Institute Infante Dom Luíz, University of Beira Interior, 6201-001 Covilhã, Portugal.
30. Aerosol and Haze Laboratory, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
31. Department of Chemistry, University of Helsinki, University of Helsinki, 00014 Helsinki, Finland.
32. Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
33. Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
34. Department of Engineering and Public Policy, Carnegie Mellon University, Pittsburgh, PA 15213, USA.