Search for lepton-flavour-violating decays of the Higgs boson

The first direct search for lepton-flavour-violating decays of the recently discovered Higgs boson (H) is described. The search is performed in the H→μτe and H→μτh channels, where τe and τh are tau leptons reconstructed in the electronic and hadronic decay channels, respectively. The data sample use...

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Detalles Bibliográficos
Autores: Missiroli, Marino, Albajar Molera, Carmen, Fernández Trocóniz Acha, Jorge, Morán, D.
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/675954
Acceso en línea:http://hdl.handle.net/10486/675954
https://dx.doi.org/10.1016/j.physletb.2015.07.053
Access Level:acceso abierto
Palabra clave:CMS
Higgs
Lepton-flavour-violation
Muons
Taus
Physics
Física
Descripción
Sumario:The first direct search for lepton-flavour-violating decays of the recently discovered Higgs boson (H) is described. The search is performed in the H→μτe and H→μτh channels, where τe and τh are tau leptons reconstructed in the electronic and hadronic decay channels, respectively. The data sample used in this search was collected in pp collisions at a centre-of-mass energy of √s=8 TeV with the CMS experiment at the CERN LHC and corresponds to an integrated luminosity of 19.7 fb-1. The sensitivity of the search is an order of magnitude better than the existing indirect limits. A slight excess of signal events with a significance of 2.4 standard deviations is observed. The p-value of this excess at MH=125 GeV is 0.010. The best fit branching fraction is B(H→μτ)=(0.84-0.37+0.39)%. A constraint on the branching fraction, B(H→μτ)<1.51% at 95% confidence level is set. This limit is subsequently used to constrain the μ-τ Yukawa couplings to be less than 3.6×10-3