Institution: | Institute of Atomic Physics and Spectroscopy, Department of Physics, University of Latvia, Rai?a bulvāris 19, LV-1586 Rīga, Latvia;Special Astrophysical Observatory, Nizhnij Arkhyz, 369167, Russia;ICAMER, National Academy of Sciences of Ukraine, 361605 Peak Terskol, Kabardino-Balkaria, Russia |