1. Czech Technical University in Prague, Faculty of Electrical Engineering, Prague, Technicka 2, 16627, Czech Republic
2. Institute of High Current Electronics, Siberian Branch of Russian Academy of Sciences, Akademichesky Avenue 2/3, 634055 Tomsk, Russia
3. National Research Tomsk Polytechnic University, Lenina Avenue 30, 634050 Tomsk, Russia
4. Nuclear Physics Institute, Czech Academy of Sciences, Na Truhlarce 39, Prague 8, Czech Republic