1. West Department of Pushkov IZMIRANRAS Kaliningrad Russia
2. Institute of Physics and TechnologyImmanuel Kant Baltic Federal University Kaliningrad Russia
3. High Altitude ObservatoryNational Center for Atmospheric Research Boulder Colorado USA
4. Haystack ObservatoryMassachusetts Institute of Technology Westford Massachusetts USA
5. Institute of Solar‐Terrestrial Physics Irkutsk Russia