[1] CERN, CH-1211 GENEVA 23, SWITZERLAND
[2] UNIV ANCONA, I-60100 ANCONA, ITALY
[3] DAPNIA, SACLAY, FRANCE
[4] INFN ROME, ANCONA, ITALY
[5] INFN BOLOGNA, ANCONA, ITALY
[6] INFN ROME, ENEA CASACCIA, ROME, ITALY
[7] IFA, INST ATOM PHYS, BUCHAREST, ROMANIA
[8] INST PHYS, PRAGUE, CZECHOSLOVAKIA
[9] IPN, IN2P3, CNRS, LYON, FRANCE
[10] ST PETERSBURG NUCL PHYS INST, ST PETERSBURG, RUSSIA
[11] BROOKHAVEN NATL LAB, UPTON, NY 11973 USA
[12] UNIV LYON 1, F-69365 LYON 2, FRANCE
[13] LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA
[14] TATA INST FUNDAMENTAL RES, BOMBAY 400005, INDIA
[15] RHEIN WESTFAL TH AACHEN, INST PHYS, W-5100 AACHEN, GERMANY
[16] UNIV LYON 1, F-69621 VILLEURBANNE, FRANCE
[17] CNRS, LPCML, F-69373 LYON, FRANCE
[18] TATA INST FUNDAMENTAL RES, BOMBAY 400005, INDIA
[19] CNRS, IN2P3, LAPP, ANNECY LE VIEUX, FRANCE