[1] Institute of Nuclear Research of the Hungarian Academy of Sciences,
[2] H-4001 Debrecen,undefined
[3] Hungary,undefined
[4] Institute for Physical and Chemical Research,undefined
[5] Wako,undefined
[6] Saitama 351-0106,undefined
[7] Japan ,undefined
[8] Department of Physics,undefined
[9] Faculty of Science,undefined
[10] Niigata University,undefined
[11] Niigata 950-2181,undefined
[12] Japan,undefined
[13] Graduate School of Science and Technology,undefined
[14] Niigata University,undefined
[15] Niigata 950-2181,undefined
[16] Japan,undefined