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arXiv · 0903.5059

Hints for the scale of new CP-violating physics from B-CP anomalies

E. Lunghi·A. Soni
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Abstract

We consider several hints for new physics involving CP-asymmetries in B-decays and interpret them in terms of generic contributions to effective Wilson coefficients. The effects we focus on are: the differences in the fitted value of sin(2 beta) versus the ones directly measured via the time dependent CP asymmetries in B -> J/psi K or via B -> (phi,eta') K; the difference between the direct CP asymmetries in B- -> K- pi0 and B0 -> K- pi+ and the ~2.2 sigma indications for the CP-asymmetry in Bs -> J/psi phi. To alleviate concerns regarding the disagreement between inclusive and exclusive Vub, we show that our results hold even without the inclusion of Vub in the analysis. We find that no matter what kind of new physics (NP) is invoked to explain these effects, its effective scale is bounded from above from a few hundred GeV to a few TeV depending on specific assumptions regarding the type of new physics. The only exception to this is when the NP contribution is assumed to reside entirely in LR operators in K mixing, then the scale of NP can be as high as around 24 TeV; however, this case cannot account for CP asymmetry in Bs -> J/psi phi or a difference in sin(2 beta) from penguin modes compared to that from J/psi K or for that matter the large difference seen between direct CP asymmetries in K- pi+ and in K- pi0.

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E. Lunghi, A. Soni. 2009-08-21. Hints for the scale of new CP-violating physics from B-CP anomalies. https://doi.org/10.1088/1126-6708%2F2009%2F08%2F051

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