1. Laboratory of Atmospheric
Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland
2. Department of Physics, University of Helsinki, Helsinki 00014, Finland
3. Institute
for Atmospheric and Environmental Sciences, Goethe University Frankfurt am Main, Frankfurt am Main 60438, Germany
4. Laboratoire de Physique des Lasers, Atomes et Molécules, Université Lille 1 Sciences et Technologies, Villeneuve d’Ascq cedex 59655, France
5. CENTRA-SIM, U. Lisboa and U. Beira Interior, Lisbon 1749, Portugal
6. CERN, Geneva 1211, Switzerland
7. University of Innsbruck, Innsbruck 6020, Austria
8. IONICON Analytik GmbH, Innsbruck 6020, Austria
9. Helsinki Institute of Physics, Helsinki 00014, Finland
10. California Institute of Technology, Pasadena, California 91125, United States
11. Department of Applied Physics, University of Eastern Finland, Kuopio 70211, Finland
12. Finnish Meteorological Institute, Helsinki 00101, Finland
13. Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, Colorado 80301, United States
14. Airmodus Ltd, Helsinki 00560, Finland
15. Lebedev Physical Institute RAS, Leninsky prospekt, Moscow 119991, Russian
16. Faculty of Physics, University of Vienna, Vienna 1090, Austria
17. Center for Atmospheric
Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
18. Aerodyne Research Inc., Billerica, Massachusetts 01821, United States