[1] European Gravitat Observ EGO, I-56021 Cascina, Pi, Italy
[2] Univ Paris 11, CNRS, IN2P3, LAL, F-91898 Orsay, France
[3] Observ Cote Azur, CNRS, Dept Artemis, F-06304 Nice, France
[4] Univ Roma La Sapienza, INFN, I-00185 Rome, Italy
[5] Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy
[6] Univ Pisa, Ist Nazl Fis Nucl, I-56127 Pisa, Italy
[7] Ist Nazl Fis Nucl, Sez Pisa, I-56127 Pisa, Italy
[8] Univ Siena, INFN, I-53100 Siena, Italy
[9] Univ Salerno, INFN, I-84084 Salerno, Italy
[10] Univ Naples Federico 2, INFN, I-80126 Naples, Italy
[11] Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England
[12] CNRS, IN2P3, Lab Mat Avances LMA, F-69622 Lyon, France
[13] Ist Nazl Fis Nucl, Sez Genova, I-16146 Genoa, Italy
[14] Univ Padua, INFN, I-35131 Padua, Italy
[15] Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy
[16] Univ Trent, INFN, I-38050 Trento, Italy
[17] Ist Nazl Fis Nucl, Grp Coll Trento, I-38050 Trento, Italy
[18] Univ Aquila, INFN, I-67100 Laquila, Italy
[19] Univ Roma Tor Vergata, INFN, I-00133 Rome, Italy
[20] Ist Nazl Fis Nucl, Sez Roma Tor Vergata, I-00133 Rome, Italy
[21] Ist Fis Spazio Interplanetario IFSI INAF, INFN, I-00133 Rome, Italy
[22] ESPCI, CNRS, F-75005 Paris, France
[23] Univ Perugia, INFN, I-6123 Perugia, Italy
[24] Ist Nazl Fis Nucl, Sez Perugia, I-6123 Perugia, Italy
[25] Univ Urbino Carlo Bo, INFN, I-61029 Urbino, Italy
[26] INFN, Sez Firenze, I-50019 Sesto Fiorentino, Italy
[27] Vrije Univ Amsterdam, Natl Inst Subatom Phys, NL-1081 HV Amsterdam, Netherlands
[28] Natl Inst Subatom Phys, NL-1009 DB Amsterdam, Netherlands
[29] Univ Savoie, Lab Annecy Le Vieux Phys Particules, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
[30] Univ Paris 07, Observ Paris, AstroParticule & Cosmol APC, CEA DSM IRFU,CNRS IN2P3 UMR7164, F-75221 Paris 05, France
[31] Ist Nazl Fis Nucl, Sez Napoli, I-80126 Naples, Italy