[1] Univ Tsukuba, Sch Pure & Appl Sci, Tsukuba, Ibaraki 3058571, Japan
[2] Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA
[3] Instrumentat Div, Upton, NY 11973 USA
[4] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England
[5] Univ Freiburg, Inst Phys, D-79104 Freiburg, Germany
[6] Univ Geneva, Sect Phys, CH-1211 Geneva, Switzerland
[7] Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland
[8] High Energy Accelerator Org, KEK, INPS, Tsukuba, Ibaraki 3050801, Japan
[9] Univ Lancaster, Dept Phys, Lancaster LA1 4YB, England
[10] Univ Liverpool, Oliver Lodge Lab, Dept Phys, Liverpool L69 7ZE, Merseyside, England
[11] Univ Ljubljana, Jozef Stefan Inst, Ljubljana, Slovenia
[12] Univ Ljubljana, Dept Phys, Ljubljana 61000, Slovenia
[13] Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA
[14] Charles Univ Prague, Fac Math & Phys, Prague 8, Czech Republic
[15] Acad Sci Czech Republ, Inst Phys, Prague 18221 8, Czech Republic
[16] UC Santa Cruz, SCIPP, Santa Cruz, CA 95064 USA
[17] Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England
[18] SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA
[19] UVEG, IFIC, Ctr Mixto, CSIC, Valencia 46071, Spain