Precision Measurement of CP Violation in B0S→J/ΨK+K− Decays

The time-dependent CP asymmetry in B0s→J/ψK+K− decays is measured using pp collision data, corresponding to an integrated luminosity of 3.0  fb−1, collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. In a sample of 96 000 B0s→J/ψK+K− decays, the CP-violating phase ϕs is measur...

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Detalles Bibliográficos
Autores: Badalov, Alexey, Calvo Gómez, Míriam, Vilasís 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:20.500.14342/3091
Acceso en línea:http://hdl.handle.net/20.500.14342/3091
https://doi.org/10.1103/PhysRevLett.114.041801
Access Level:acceso abierto
Palabra clave:Gran col·lisionador d'hadrons (França i Suïssa)
Partícules (Física nuclear)
Col·lisions (Física nuclear)
539
Descripción
Sumario:The time-dependent CP asymmetry in B0s→J/ψK+K− decays is measured using pp collision data, corresponding to an integrated luminosity of 3.0  fb−1, collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. In a sample of 96 000 B0s→J/ψK+K− decays, the CP-violating phase ϕs is measured, as well as the decay widths ΓL and ΓH of the light and heavy mass eigenstates of the B0s–¯B0s system. The values obtained are ϕs=−0.058±0.049±0.006  rad, Γs≡(ΓL+ΓH)/2=0.6603±0.0027±0.0015  ps−1, and ΔΓs≡ΓL−ΓH=0.0805±0.0091±0.0032  ps−1, where the first uncertainty is statistical and the second, systematic. These are the most precise single measurements of those quantities to date. A combined analysis with B0s→J/ψπ+π− decays gives ϕs=−0.010±0.039  rad. All measurements are in agreement with the standard model predictions. For the first time, the phase ϕs is measured independently for each polarization state of the K+K− system and shows no evidence for polarization dependence.