1. Department of Physics, St. Petersburg State University, Universitetskaya 7/9, 199034 St. Petersburg, Russia
2. Joint Institute for Nuclear Research, ul. Joliot-Curie 6, 141980 Dubna, Moscow oblast, Russia
3. Helmholtzzentrum für Schwerionenforschung GmbH, Planckstr. 1, D-64291 Darmstadt, Germany
4. Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 97401 Banská Bystrica, Slovakia