1. Space Research Institute of Russian Academy of Sciences, Moscow 117997, Russia
2. Faculty of Physics, National Research University Higher School of Economics, Moscow 101000, Russia
3. Space Sciences Laboratory, University of California at Berkeley, Berkeley, California 94720, USA
4. Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90095, USA
5. Department of Physics, Moscow State University, Moscow 119234, Russia