Search for the rare leptonic decays B+ → l+ νl (l = e, μ)

We have performed a search for the rare leptonic decays B+ -> l(+) nu(l)(l = e, mu), using data collected at the Upsilon(4S) resonance by the BABAR detector at the PEP-II storage ring. In a sample of 468 x 10(6) B (B) over bar pairs we find no evidence for a signal and set an upper limit on the branching fractions B(B+ -> mu(+)nu(mu)) < 1.0 x 10(-6) and B(B+ -> e(+) nu(e)) < 1.9 x 10(-6) at the 90% confidence level, using a Bayesian approach.