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

The time-dependent C P asymmetry in B 0 s → J / ψ K + K − decays is measured using p p 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 B 0 s → J / ψ K + K − decays, the C P...

Descripción completa

Detalles Bibliográficos
Autores: Badalov, Alexey, Calvo Gómez, Míriam, Casanova Mohr, Raimon, Garrido Beltrán, Lluís, Gascón Fora, David, Graciani Díaz, Ricardo, Graugés Pous, Eugeni, Marin Benito, Carla, Picatoste Olloqui, Eduardo, Rives Molina, Vicente José, Ruiz, Hugo (Ruiz Pérez), Vilasis-Cardona, Xavier, LHCb Collaboration
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:2445/132916
Acceso en línea:https://hdl.handle.net/2445/132916
Access Level:acceso abierto
Palabra clave:Física de partícules
Experiments
Particle physics
Descripción
Sumario:The time-dependent C P asymmetry in B 0 s → J / ψ K + K − decays is measured using p p 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 B 0 s → J / ψ K + K − decays, the C P -violating phase ϕ s is measured, as well as the decay widths Γ L and Γ H of the light and heavy mass eigenstates of the B 0 s - ¯ B 0 s system. The values obtained are ϕ s = − 0.058 ± 0.049 ± 0.006     rad , Γ s ≡ ( Γ L + Γ H ) / 2 = 0.6603 ± 0.0027 ± 0.0015     ps − 1 , and Δ Γ s ≡ Γ L − Γ H = 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 B 0 s → J / ψ π + π − decays gives ϕ s = − 0.010 ± 0.039     rad . All measurements are in agreement with the standard model predictions. For the first time, the phase ϕ s is measured independently for each polarization state of the K + K − system and shows no evidence for polarization dependence.