Return to search

A search for the decays B⁺ [arrow] l⁺[nu] and B⁰ [arrow] l⁺ [tau]⁻ (l = e, [mu]) using hadronic tag reconstruction /

We present searches for the leptonic decays B + → ℓ+nu and the lepton flavor violating decays B0 → ℓ+/-tau ∓, where ℓ = e, mu, with data collected by the BABAR experiment at SLAC. These searches utilize a technique in which we fully reconstruct the accompanying B¯ in Upsilon(4S) → BB¯ events, and look for a monoenergetic lepton in the signal B frame. The signal yield in the data 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 million BB¯ pairs (342 fb-1), we find no evidence of signal in any of the decay modes. Branching fraction upper limits of B (B+ → e +nu) < 5.2 x 10-6, B (B+ → mu+nu) < 5.6 x 10-6, B (B0 → e +tau-) < 2.8 x 10-5 and B (B0 → mu+tau -) < 2.2 x 10-5, are obtained at the 90% confidence level.

Identiferoai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.112525
Date January 2007
CreatorsKlemetti, Miika A.
PublisherMcGill University
Source SetsLibrary and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada
LanguageEnglish
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Formatapplication/pdf
CoverageMaster of Science (Department of Physics.)
RightsAll items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated.
Relationalephsysno: 002712108, proquestno: AAIMR51293, Theses scanned by UMI/ProQuest.

Page generated in 0.0019 seconds