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 ρ and η, by means of a global CKM fit. The fit is dominated by the precision measurement of sin 2β by the B factories. A detailed numerical and graphical study of the impact of the results is presented. We propose to include sin 2α from the recent measurement of the time-dependent CP -violating asymmetries in B 0 → ρ + ρ − , using isospin relations to discriminate the penguin contribution. The constraint from ε ′ /ε is discussed. We study the impact from the branching fraction measurement of the rare kaon decay K + → π + νν, and give an outlook into the reach of a future measurement of K 0 L → π 0 νν. The B system is investigated in detail. We display the constraint on 2β + γ and γ from B 0 → D ( * )± π ∓ 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 ππ, Kπ, ρπ, ρρ and modes related to these by flavor symmetry. Various phenomenological approaches and theoretical frameworks are discussed. We find a remarkable agreement of the ππ and Kπ 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 ππ and Kπ data leads to precise predictions of the related observables. However sizable phenomenological power corrections are preferred. Using an isospin-based phenomenological parameterization, we analyze separately the B → Kπ decays, and the impact of electroweak penguins in response to recent discussions. We find that the present data are not sufficiently precise to constrain either electroweak parameters or 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 B 0 B 0 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 ∆m s from the experimental information on B 0 s B 0 s 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 analysis package CKMfitter, featuring the frequentist statistical approach Rfit.
The LHCb experiment is dedicated to precision measurements of CP violation and rare decays of B hadrons at the Large Hadron Collider (LHC) at CERN (Geneva). The initial configuration and expected performance of the detector and associated systems, as established by test beam measurements and simulation studies, is described.
The paper advocates the use of a statistical tool dedicated to the exploration of data samples populated by several sources of events. This new technique, called s Plot, is able to unfold the contributions of the different sources to the distribution of a data sample in a given variable. The s Plot tool applies in the context of a Likelihood fit which is performed on the data sample to determine the yields of the various sources.
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