[1] Gesell Schwerionenforsch mbH, D-64291 Darmstadt, Germany
[2] Inst Theoret Phys 1, D-35392 Giessen, Germany
[3] Chalmers Tekn Hgsk, Fys Inst, S-41296 Gothenburg, Sweden
[4] Aarhus Univ, Inst Fys & Astron, DK-8000 Aarhus C, Denmark
[5] CSIC, Inst Estructura Mat, E-28006 Madrid, Spain
[6] Comenius Univ, Bratislava 84215, Slovakia
[7] CERN, Div EP, CH-1211 Geneva 23, Switzerland
[8] RIKEN, Wako, Saitama 35101, Japan
[9] Tech Univ Darmstadt, Inst Kernphys, D-64289 Darmstadt, Germany
[10] Univ Giessen, Inst Phys 2, D-35392 Giessen, Germany