[1] Univ Napoli Federico II, Dipartimento Fis Ettore Pancini, Complesso Univ Monte S Angelo,Via Cinthia Edificio, I-80126 Naples, Italy
[2] Scuola Super Meridionale, Largo San Marcellino 10, I-80138 Naples, Italy
[3] Ist Nazl Fis Nucl, Sez Napoli, Complesso Univ Monte S Angelo,Via Cinthia Edificio, I-80126 Naples, Italy
[4] Al Farabi Kazakh Natl Univ, Dept Phys & Tech, Al Farabi Ave 71, Alma Ata 050040, Kazakhstan
[5] Univ Camerino, Sch Sci & Technol, Via Madonna Carceri 9, I-62032 Camerino, Italy
[6] SUNY Coll Technol Utica, Polytech Inst, Utica, NY 13502 USA
[7] Ist Nazl Fis Nucl INFN, Sez Perugia, Via A Pascoli, I-06123 Perugia, Italy
[8] INAF Osservatorio Astron Brera, Milan, Italy