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Complete analysis of all $B\to \pi K$ decays.
TL;DR: In this article, a combined Bayesian analysis with the topological amplitudes and their phases as the free parameters is presented, showing that the best-fit region has a large overlap with the parameter space favored in the SM, albeit with some enhancement for the electroweak penguin and the colour-suppressed tree amplitudes, consistent with the findings of earlier studies.
Abstract: The Standard Model (SM) predicts that $\Delta A_{\rm CP}$, the difference between the direct CP asymmetries for the modes $B^+\to \pi^0 K^+$ and $B^0\to \pi^- K^+$ that are related by weak isospin, should be close to zero. There has been a recent claim by the LHCb Collaboration that the measured value of $\Delta A_{\rm CP}$ shows an uncomfortable tension with the SM prediction, almost at the $8\sigma$ level. Motivated by this claim, we critically re-examine the data on all the $B\to \pi K$ modes, including the CP asymmetries and CP-averaged branching fractions. From a combined Bayesian analysis with the topological amplitudes and their phases as the free parameters, we find that the best-fit region has a large overlap with the parameter space favoured in the SM, albeit with some enhancement for the electroweak penguin and the colour-suppressed tree amplitudes, consistent with the findings of earlier studies. We find that in this SM-like region, $\Delta A_{\rm CP}$ is more than 5$\sigma$ away from zero and the tension with the global average, as well as the LHCb result, is within $2\sigma$. Thus we conclude that there is not yet enough motivation to go beyond the SM.
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TL;DR: In this article, a modified Monte Carlo integration over configuration space is used to investigate the properties of a two-dimensional rigid-sphere system with a set of interacting individual molecules, and the results are compared to free volume equations of state and a four-term virial coefficient expansion.
Abstract: A general method, suitable for fast computing machines, for investigating such properties as equations of state for substances consisting of interacting individual molecules is described. The method consists of a modified Monte Carlo integration over configuration space. Results for the two‐dimensional rigid‐sphere system have been obtained on the Los Alamos MANIAC and are presented here. These results are compared to the free volume equation of state and to a four‐term virial coefficient expansion.
35,161 citations
TL;DR: In this paper, the authors review the present status of QCD corrections to weak decays beyond the leading-logarithmic approximation, including particle-antiparticle mixing and rare and $\mathrm{CP}$-violating decays.
Abstract: We review the present status of QCD corrections to weak decays beyond the leading-logarithmic approximation, including particle-antiparticle mixing and rare and $\mathrm{CP}$-violating decays. After presenting the basic formalism for these calculations we discuss in detail the effective Hamiltonians of all decays for which the next-to-leading-order corrections are known. Subsequently, we present the phenomenological implications of these calculations. The values of various parameters are updated, in particular the mass of the newly discovered top quark. One of the central issues in this review are the theoretical uncertainties related to renormalization-scale ambiguities, which are substantially reduced by including next-to-leading-order corrections. The impact of this theoretical improvement on the determination of the Cabibbo-Kobayashi-Maskawa matrix is then illustrated. [S0034-6861(96)00304-2]
2,277 citations
TL;DR: In this paper, the authors report world averages of measurements of b-hadron, c-, c-, and tau-lepton properties obtained by the Heavy Flavor Averaging Group (HFAG) using results available through the end of 2011.
Abstract: This article reports world averages of measurements of b-hadron, c-hadron, and tau-lepton properties obtained by the Heavy Flavor Averaging Group (HFAG) using results available through the end of 2011. In some cases results available in the early part of 2012 are included. For the averaging, common input parameters used in the various analyses are adjusted (rescaled) to common values, and known correlations are taken into account. The averages include branching fractions, lifetimes, neutral meson mixing parameters, CP violation parameters, parameters of semileptonic decays and CKM matrix elements.
2,151 citations
TL;DR: In this article, a comprehensive study of exclusive hadronic B -meson decays into final states containing two pseudoscalar mesons (PP) and a vector meson (PV) is presented.
797 citations
TL;DR: In this paper, the branching ratios of quark decay amplitudes with universal meson wave functions were derived for tree, penguin, and annihilation modes in the framework of the perturbative QCD factorization theorem.
Abstract: We compute the branching ratios of $\stackrel{\ensuremath{\rightarrow}}{B}K\ensuremath{\pi}$ decays in the framework of the perturbative QCD factorization theorem. Decay amplitudes are classified into the topologies of tree, penguin, and annihilation amplitudes, all of which contain both factorizable and nonfactorizable contributions. These contributions are expressed as the convolutions of hard $b$ quark decay amplitudes with universal meson wave functions. It is shown that (1) matrix elements of penguin operators are dynamically enhanced compared to those employed in the factorization assumption, (2) annihilation diagrams are not negligible, contrary to common belief, (3) annihilation diagrams contribute large strong phases, and (4) the uncertainty of the current data of the ratio $R=\mathrm{Br}{(B}_{d}^{0}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}})/\mathrm{Br}{(B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{0}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}})$ and of $\mathrm{CP}$ asymmetries is too large to give a constraint of the unitarity angle ${\ensuremath{\varphi}}_{3}.$ Assuming ${\ensuremath{\varphi}}_{3}=90\ifmmode^\circ\else\textdegree\fi{}$ which is extracted from the best fit to the data of $R,$ predictions for the branching ratios of the four $\stackrel{\ensuremath{\rightarrow}}{B}K\ensuremath{\pi}$ modes are consistent with data.
490 citations