1. Department of Physics, Moscow State University, 1-2 Leninskie Gory, Moscow 119991, Russia
2. Space Research Institute of the Russian Academy of Sciences (IKI), 84/32 Profsoyuznaya Str., Moscow 117997, Russia
3. Department of Earth, Planetary, and Space Sciences, University of California, 595 Charles E Young Dr E, Los Angeles, California 90095, USA
4. Faculty of Physics, National Research University Higher School of Economics, 21/4 Staraya Basmannaya Ulitsa, Moscow 105066, Russia
5. Space Sciences Laboratory, University of California at Berkeley, 7 Gauss Way, Berkeley, California 94720, USA