[1] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA
[2] Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA
[3] INFN Lab Nazl Gran Sasso, I-67010 Laquila, Italy
[4] INFN Lab Nazl Legnaro, I-35020 Padua, Italy
[5] Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA
[6] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Nucl Sci Div, Berkeley, CA 94720 USA
[7] INFN Sez Bologna, I-40127 Bologna, Italy
[8] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA
[9] Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy
[10] INFN Sez Roma, I-00185 Rome, Italy
[11] INFN Sez Genova, I-16146 Genoa, Italy
[12] Univ Milano Bicocca, Dipartimento Fis, I-20126 Milan, Italy
[13] INFN Sez Milano Bicocca, I-20126 Milan, Italy
[14] Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai 201800, Peoples R China
[15] Univ Cassino & Lazio Meridionale, Dipartimento Ingn Civile & Meccan, I-03043 Cassino, Italy
[16] Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy
[17] Yale Univ, Dept Phys, New Haven, CT 06520 USA
[18] Univ Wisconsin, Dept Phys, Madison, WI 53706 USA
[19] INFN Gran Sasso Sci Inst, I-67100 Laquila, Italy
[20] Univ Aquila, Dipartimento Sci Fis & Chim, I-67100 Laquila, Italy
[21] CSNSM, F-91405 Orsay, France
[22] Calif Polytech State Univ San Luis Obispo, Dept Phys, San Luis Obispo, CA 93407 USA
[23] Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA
[24] MIT, Cambridge, MA 02139 USA
[25] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA
[26] Univ Zaragoza, Lab Fis Nucl & Astroparticulas, E-50009 Zaragoza, Spain
[27] Univ Bologna, Alma Mater Studiorum, Dipartimento Sci Qualita Vita, I-47921 Bologna, Italy
[28] CEA, Ctr Saclay, Irfu SPP, F-91191 Gif Sur Yvette, France
[29] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA
[30] Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA
[31] INFN Sez Padova, I-35131 Padua, Italy
[32] Univ Florence, Dipartimento Fis, I-50125 Florence, Italy
[33] INFN Sez Firenze, I-50125 Florence, Italy
[34] Univ Bologna, Alma Mater Studiorum, Dipartimento Fis & Astron, I-40127 Bologna, Italy