Measurement of CP-violating asymmetries in B0 → (ρπ)0 decays using a time-dependent Dalitz plot analysis

We present results for a time-dependent Dalitz plot measurement of C P -violating asymmetries in the mode B 0 → π + π − π 0 . The data set is derived from the complete sample of 471 × 10 6 B ¯¯¯ B meson pairs collected with the BABAR detector at the PEP-II asymmetric-energy e + e − collider at the S...

Descripción completa

Detalles Bibliográficos
Autores: Graugés Pous, Eugeni, BABAR Collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/131842
Acceso en línea:https://hdl.handle.net/2445/131842
Access Level:acceso abierto
Palabra clave:Física de partícules
Experiments
Violació CP (Física nuclear)
Particle physics
CP violation (Nuclear physics)
Descripción
Sumario:We present results for a time-dependent Dalitz plot measurement of C P -violating asymmetries in the mode B 0 → π + π − π 0 . The data set is derived from the complete sample of 471 × 10 6 B ¯¯¯ B meson pairs collected with the BABAR detector at the PEP-II asymmetric-energy e + e − collider at the SLAC National Accelerator Laboratory operating on the Υ ( 4 S ) resonance. We extract parameters describing the time-dependent B 0 → ρ π decay probabilities and C P asymmetries, including C = 0.016 ± 0.059 ± 0.036 , Δ C = 0.234 ± 0.061 ± 0.048 , S = 0.053 ± 0.081 ± 0.034 , and Δ S = 0.054 ± 0.082 ± 0.039 , where the uncertainties are statistical and systematic, respectively. We perform a two-dimensional likelihood scan of the direct C P -violation asymmetry parameters for B 0 → ρ ± π ∓ decays, finding the change in χ 2 between the minimum and the origin (corresponding to no direct C P violation) to be Δ χ 2 = 6.42 . We present information on the C P -violating parameter α in a likelihood scan that incorporates B ± → ρ π measurements. To aid in the interpretation of our results, statistical robustness studies are performed to assess the reliability with which the true values of the physics parameters can be extracted. Significantly, these studies indicate that α cannot be reliably extracted with our current sample size, though the other physics parameters are robustly extracted.