Search For The Rare Leptonic Decay B Tau Nubar

We present a search for the decay B− →?− {bar {nu}}{sub?} in a sample of 88.9 x 106 B{bar B}pairs recorded with the BABAR detector at the SLAC B-Factory. One of the two B mesons from the?(4S) is reconstructed in a hadronic or a semileptonic final state and the decay products of the other B in the event are analyzed for consistency with a B− →?− {bar {nu}}{sub {tau}} decay. We find no evidence of a signal and set an upper limit on the branching fraction of?(B− → {tau}− {bar {nu}}{sub {tau}})