[1] Stefan Meyer Inst Subatomare Phys, A-1090 Vienna, Austria
[2] Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Rome, Italy
[3] Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada
[4] Politecn Milan, Dip Elettron & Informaz, I-20133 Milan, Italy
[5] Inst Natl Pentru Fiz Si Ingn Nucl Horia Hulubei, Magurele, Romania
[6] Ist Nazl Fis Nucl, Sez Roma 1, I-00161 Rome, Italy
[7] Inst Super Sanita, I-00161 Rome, Italy
[8] Univ Tokyo, Bunkyo Ku, Tokyo 113, Japan
[9] RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan
[10] Tech Univ Munich, Excellence Cluster Universe, D-85748 Garching, Germany
[11] Univ Santiago de Compostela, Santiago De Compostela 15782, Spain