1. Laboratoire de Physicochimie de l'Atmosphère, Université du Littoral Côte d'Opale, 189A, Av. Maurice Schumann, 59140 Dunkerque, France
2. Laboratory of Atmospheric Physico-Chemistry, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 1125, 350 Shushanhu Road, Hefei, Anhui 230031, China
3. ETH Zurich, Institute for Quantum Electronics, HPT H4.1, Auguste-Piccard-Hof 1, CH-8093 Zürich, Switzerland