1. National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow, Russia
2. N.I. Lobachevsky Institute of Mathematics and Mechanics, Kazan Federal University, Kremlevskaya street 18, 420008 Kazan, Russia
3. Dipartimento di Fisica “E.R. Caianiello”, Università degli Studi di Salerno, Via Giovanni Paolo II, 132, 84084, Salerno, Italy