ADEVA, B (reprint author), CERN,EUROPEAN LAB PARTICLE PHYS,CH-1211 GENEVA 23,SWITZERLAND.
From a fit to the impact parameter distribution of lepton tracks from semileptonic b decay, the lifetime of B-hadrons produced in e+e- collisions at the Z0 is measured to be 1.32 +/- 0.08 (stat.) +/- 0.09 (syst.) ps. Combined with an earlier measurement of the branching ratio Br(B --> lvX), the CKM matrix element \V(cb)\ is determined to be 0.046 +/- 0.002 (exp.) -0.003(+0.004) (theory).