1. Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland
2. Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
3. CNR-IPCF, Largo Bruno Pontecorvo 3, I-56127 Pisa, Italy