Search for B+-->[script l]+ν[script l] recoiling against B -->D0[script l]- [v over-bar]X

• Main Authors: Cowan, Ray Franklin (Contributor), Dujmic, Denis (Contributor), Fisher, Peter H. (Contributor), Henderson, Shawn Wesley (Contributor), Sciolla, Gabriella (Contributor), Spitznagel, M. (Contributor), Yamamoto, Richard K. (Contributor), Zhao, M. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor), Massachusetts Institute of Technology. Laboratory for Nuclear Science (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2010-10-08T17:36:00Z.
• Subjects: Article
• Online Access: Get fulltext

We present a search for the decay B+→ℓ+νℓ(ℓ=τ,μ, or e) in (458.9±5.1)×106 BB̅ pairs recorded with the BABAR detector at the PEP-II B-factory. We search for these B decays in a sample of B+B- events where one B-meson is reconstructed as B-→D0ℓ-ν̅ X. Using the method of Feldman and Cousins, we obtain B(B+→τ+ντ)=(1.7±0.8±0.2)×10-4, which excludes zero at 2.3σ. We interpret the central value in the context of the standard model and find the B meson decay constant to be fB2=(62±31)×103  MeV2. We find no evidence for B+→e+νe and B+→μ+νμ and set upper limits at the 90% C.L. B(B+→e+νe)<0.8×10-5 and B(B+→μ+νμ)<1.1×10-5.
United States. Dept. of Energy
Natural Sciences and Engineering Research Council Canada
France. Commissariat à l'énergie atomique
Institut national de physique nucléaire et de physique des particules
Germany. Bundesministerium für Bildung und Forschung
Deutsche Forschungsgemeinschaft
Istituto nazionale di fisica nucleare
Stichting voor Fundamenteel Onderzoek der Materie
Norges forskningsråd
Russia (Federation). Ministerstvo obrazovanii︠a︡ i nauki
Spain. Ministerio de Educación y Ciencia
Science and Technology Facilities Council (Great Britain)
Marie Curie International Fellowship
Alfred P. Sloan Foundation
National Science Foundation (U.S.)