Measurement of the Ratio of Branching Fractions B(¯B0→D*+τ−¯ντ)/B(¯B0→D*+μ−¯νμ)

The branching fraction ratio R(D∗)≡B(¯B0→D*+τ−¯ντ)/B(¯B0→D*+μ−¯νμ) is measured using a sample of proton-proton collision data corresponding to 3.0  fb−1 of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ−→μ−¯νμντ. The semit...

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Detalles Bibliográficos
Autores: Badalov, Alexey, Calvo Gomez, Miriam, Vilasis-Cardona, Xavier, LHCb Collaboration - CERN
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:20.500.14342/3300
Acceso en línea:http://hdl.handle.net/20.500.14342/3300
https://doi.org/10.1103/PhysRevLett.115.111803
Access Level:acceso abierto
Palabra clave:Gran col·lisionador d'hadrons (França i Suïssa)
Partícules (Física nuclear)
Protons
Col·lisions (Física nuclear)
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Descripción
Sumario:The branching fraction ratio R(D∗)≡B(¯B0→D*+τ−¯ντ)/B(¯B0→D*+μ−¯νμ) is measured using a sample of proton-proton collision data corresponding to 3.0  fb−1 of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ−→μ−¯νμντ. The semitauonic decay is sensitive to contributions from non-standard-model particles that preferentially couple to the third generation of fermions, in particular, Higgs-like charged scalars. A multidimensional fit to kinematic distributions of the candidate ¯B0 decays gives R(D∗)=0.336±0.027(stat)±0.030(syst). This result, which is the first measurement of this quantity at a hadron collider, is 2.1 standard deviations larger than the value expected from lepton universality in the standard model.