1. Radiation Safety Directorate , Partizanski odredi 143 P.O. Box 22, 1020 , Skopje , Macedonia
2. Institute of Physics , Faculty of Natural Sciences and Mathematics , Ss. Cyril and Methodius University in Skopje , P.O. Box 162, 1001 , Skopje , Macedonia
3. Research Center for Computer Science and Information Technologies Macedonian Academy of Sciences and Arts Bul , Krste Misirkov 2, 1000 , Skopje , Macedonia
4. Institute for Physics and Astronomy , Karl-Liebknecht-St. 24/25 , University of Potsdam , D-14776 , Potsdam-Golm , Germany
5. Akhiezer Institute for Theoretical Physics , Akademicheskaya St. 1 , Kharkov , 61108 , Ukraine