Searches for the decays B-0 -> l(+/-)tau(-/+) and B+-> l(+)nu (l = e, mu) using hadronic tag reconstruction

We present searches for the leptonic decays B+→ℓ+ν and the lepton flavor violating decays B0→ℓ±τ, where ℓ=e, μ, with data collected by the BABAR experiment at SLAC. This search demonstrates a novel technique in which we fully reconstruct the accompanying B̄ in Υ(4S)→BB̄ events, and look for a monoen...

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Bibliografske podrobnosti
Main Authors: Aubert, B, Bona, M, Karyotakis, Y, Lees, J, Poireau, V, Prudent, X, Tisserand, V, Zghiche, A, Tico, J, Grauges, E, Lopez, L, Palano, A, Pappagallo, M, Eigen, G, Stugu, B, Sun, L, Abrams, G, Battaglia, M, Brown, D, Button-Shafer, J, Cahn, R, Jacobsen, R, Kadyk, J, Kerth, LT, Kolomensky, Y
Format: Journal article
Izdano: 2008
Opis
Izvleček:We present searches for the leptonic decays B+→ℓ+ν and the lepton flavor violating decays B0→ℓ±τ, where ℓ=e, μ, with data collected by the BABAR experiment at SLAC. This search demonstrates a novel technique in which we fully reconstruct the accompanying B̄ in Υ(4S)→BB̄ events, and look for a monoenergetic lepton from the signal B decay. The signal yield is extracted from a fit to the signal lepton candidate momentum distribution in the signal B rest frame. Using a data sample of approximately 378×106 BB̄ pairs (342fb-1), we find no evidence of signal in any of the decay modes. Branching fraction upper limits of B(B+→e+ν)<5.2×10-6, B(B+→μ+ν)<5.6×10-6, B(B0→e+τ-)<2.8×10-5 and B(B0→μ+τ-)<2. 2×10-5, are obtained at 90% confidence level. © 2008 The American Physical Society.