Measurement of the average lifetime ofBhadrons produced inpp¯collisions at √s=1.8 TeV

The average b-hadron lifetime has been measured using a high statistics sample of {ital B} {r_arrow} {ital J}/{psi}{Chi} decays recorded with the Collider Detector at Fermilab. We use a sample with an integrated luminosity of {approx} 90 {ital pb}{sup -1} recorded during the 1994-95 running period. The decay vertices of {approx} 62656 inclusive {ital J}/{psi} {r_arrow} {mu}{sup +}{mu}{sup -} candidates have been reconstructed using information from a silicon vertex-detector. The measured {ital B}lifetime, which is the average over all b-hadrons produced in {ital p}{ital {anti p}} collisions at {radical}s = 1.8 TeV weighted by their branching ratios into {ital J}/{psi}, is 1.524 {+-} 0.015 ({ital stat}){sup +0.035}{sub -0.026} ({ital sys}) ps. The precision of this measurement is significantly improved compared to the inclusive lifetime measurement published previously using {approx} 10 {ital pb}{sup -1}.