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CP Violation and the CKM Matrix: Assessing the Impact of the Asymmetric B Factories

and Kpi data with the other constraints in the unitarity plane when the hadronic matrix elements are calculated within QCD Factorization, where we apply a conservative treatment of the theoretical uncertainties. A global fit of QCD Factorization to all pipi and Kpi data leads to precise predictions...

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Detalles Bibliográficos
Autores principales: Charles, J., Hocker, Andreas, Lacker, H., Laplace, S., Le Diberder, F.R., Malcles, J., Ocariz, J., Pivk, M., Roos, L.
Lenguaje:eng
Publicado: 2004
Materias:
Acceso en línea:https://dx.doi.org/10.1140/epjc/s2005-02169-1
http://cds.cern.ch/record/782079
Descripción
Sumario:and Kpi data with the other constraints in the unitarity plane when the hadronic matrix elements are calculated within QCD Factorization, where we apply a conservative treatment of the theoretical uncertainties. A global fit of QCD Factorization to all pipi and Kpi data leads to precise predictions of the related observables. Using an isospin-based phenomenological parameterization, we analyze separately the B --> Kpi decays, and the impact of electroweak penguins in response to recent discussions. We find that the present data are not sufficiently precise to constrain electroweak parameters neither hadronic amplitude ratios. We do not observe any unambiguous sign of New Physics, whereas there is some evidence for potentially large non-perturbative rescattering effects. Finally we use a model-independent description of a large class of New Physics effects in both B0/B0bar mixing and B decays, namely in the b --> d and b --> s gluonic penguin amplitudes, to perform a new numerical analysis. Significant non-standard corrections cannot be excluded yet, however Standard Model solutions are favored in most cases. In the appendix to this paper we propose a frequentist method to extract a confidence level on deltams from the experimental information on Bs/Bsbar oscillation. In addition we describe a novel approach to combine potentially inconsistent measurements. All results reported in this paper have been obtained with the numerical analyzer package CKMfitter, featuring the We present an up-to-date profile of the Cabibbo-Kobayashi-Maskawa matrix with emphasis on the interpretation of recent CP-violation results from the B factories. For this purpose, we review all relevant experimental and theoretical inputs from the contributing domains of electroweak interaction. We give the ``standard'' determination of the apex of the Unitarity Triangle, namely the Wolfenstein parameters rhobar and etabar, by means of a global CKM fit. The fit is dominated by the precision measurement of sin2beta by the B factories. A detailed numerical and graphical study of the impact of the results is presented. We propose to include sin2alpha from the recent measurement of the time-dependent CP-violating asymmetries in B0 --> rho+rho-, using isospin relations to discriminate the penguin contribution. The constraint from epsilon'/epsilon is discussed. We study the impact from the branching fraction measurement of the rare kaon decay K+ --> pi+nunubar, and give an outlook into the reach of a future measurement of KL --> pi0nunubar. The B system is investigated in detail. We display the constraint on 2beta+gamma and gamma from B0 --> D(*)+- pi-+ and B+ --> D(*)0 K+ decays, respectively. A significant part of this paper is dedicated to the understanding of the dynamics of B decays into pipi, Kpi, rhopi, rhorho and modes related to these by flavor symmetry. Various phenomenological app roaches and theoretical frameworks are discussed. We find a remarkable agreement of the pipi frequentist statistical approach Rfit.