[1] Columbia Univ, Phys Dept, New York, NY 10027 USA
[2] Univ Tokyo, Inst Cosm Ray Res, Kamioka Observ, Hida, Gifu 5061205, Japan
[3] Univ Tokyo, Kavli Inst Phys & Math Universe WPI, Hida, Gifu 5061205, Japan
[4] Univ Bologna, Dept Phys & Astron, I-40126 Bologna, Italy
[5] INFN Bologna, I-40126 Bologna, Italy
[6] Sorbonne Univ, LPNHE, CNRS IN2P3, F-75005 Paris, France
[7] Johannes Gutenberg Univ Mainz, Inst Phys & Exzellenzcluster PRISMA, D-55099 Mainz, Germany
[8] Westfalische Wilhelms Univ Munster, Inst Kernphys, D-48149 Minster, Germany
[9] Univ Torino, Dept Phys, INAF Astrophys Observ Torino, I-10125 Turin, Italy
[10] INFN Torino, I-10125 Turin, Italy
[11] Nikhef, Sci Pk, NL-1098 XG Amsterdam, Netherlands
[12] Univ Amsterdam, Sci Pk, NL-1098 XG Amsterdam, Netherlands
[13] Stockholm Univ, Oskar Klein Ctr, Dept Phys, AlbaNova, SE-10691 Stockholm, Sweden
[14] Univ Chicago, Dept Phys, Chicago, IL 60637 USA
[15] Univ Chicago, Kavli Inst Cosmol Phys, Chicago, IL 60637 USA
[16] New York Univ Abu Dhabi, Ctr Astro Particle & Planetary Phys, Abu Dhabi, U Arab Emirates
[17] Univ Zurich, Phys Inst, CH-8057 Zurich, Switzerland
[18] Purdue Univ, Dept Phys & Astron, W Lafayette, IN 47907 USA
[19] INFN Lab Nazl Gran Sasso, I-67100 Laquila, Italy
[20] Gran Sasso Sci Inst, I-67100 Laquila, Italy
[21] Univ Freiburg, Phys Inst, D-79104 Freiburg, Germany
[22] Univ Nantes, IMT Atlantique, SUBATECH, CNRS IN2P3, F-44307 Nantes, France
[23] Weizmann Inst Sci, Dept Particle Phys & Astrophys, IL-7610001 Rehovot, Israel
[24] Tsinghua Univ, Dept Phys, Beijing 100084, Peoples R China
[25] Tsinghua Univ, Ctr High Energy Phys, Beijing 100084, Peoples R China
[26] Univ Coimbra, Dept Phys, LIBPhys, P-3004516 Coimbra, Portugal
[27] Max Planck Inst Kernphys, D-69117 Heidelberg, Germany
[28] Karlsruhe Inst Technol, Inst Astroparticle Phys, D-76021 Karlsruhe, Germany
[29] Univ Aquila, Dept Phys & Chem, I-67100 Laquila, Italy
[30] Univ Napoli, Dept Phys Ettore Pancini, I-80126 Naples, Italy
[31] INFN Napoli, I-80126 Naples, Italy
[32] Rice Univ, Dept Phys & Astron, Houston, TX 77005 USA
[33] Nagoya Univ, Kobayashi Maskawa Inst Origin Particles & Univers, Chikusa Ku, Furo Cho, Nagoya, Aichi 4648602, Japan
[34] Nagoya Univ, Inst Space Earth Environm Res, Furo Cho, Nagoya, Aichi 4648602, Japan
[35] Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA
[36] Kobe Univ, Dept Phys, Kobe, Hyogo 6578501, Japan
[37] Nagoya Univ, Inst Adv Res, Nagoya, Aichi 4648601, Japan
[38] Coimbra Polytech ISEC, P-3030199 Coimbra, Portugal
[39] Heidelberg Univ, Phys Inst, Heidelberg, Germany
[40] Univ Ferrara, Ist Nazl Fis Nucl, Sez Ferrara, Via Saragat 1,Edificio C, I-44122 Ferrara, FE, Italy
[41] Univ Ferrara, Dip Fis & Sci Terra, Via Saragat 1,Edificio C, I-44122 Ferrara, FE, Italy