[1] Moscow MV Lomonosov State Univ, DV Skobeltsyn Inst Nucl Phys, Moscow 119991, Russia
[2] Univ Torino, Dept Phys, Via Pietro Giuria 1, I-10125 Turin, Italy
[3] Moscow MV Lomonosov State Univ, Fac Phys, Moscow 119991, Russia
[4] Univ Paris, CNRS, Astroparticule & Cosmol, F-75013 Paris, France
[5] CNRS, Ecole Polytechn, IN2P3, Omega, F-91128 Palaiseau, France
[6] RIKEN, Wako, Saitama 3510198, Japan
[7] INFN, Struct Rome Tor Vergata, I-00133 Rome, Italy
[8] KTH Royal Inst Technol, SE-10044 Stockholm, Sweden
[9] Natl Ctr Nucl Res, PL-90558 Lodz, Poland
[10] Ecole Polytechn Federale Lausanne, Lab Astrophys, CH-1015 Lausanne, Switzerland
[11] Univ Roma Tor Vergata, Dept Phys, I-00133 Rome, Italy