اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدA complete analysis of all $Bto pi K$ decays
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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 $B^0to pi^- K^+$ 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 $8sigma$ level. Motivated by this claim, we critically re-examine the data on all the $Bto pi K$ 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. This `SM-like region perfectly explains $Delta A_{rm CP}$ and hence we conclude that there is not yet enough motivation to go beyond the SM.
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