On the LHCb anomaly in BK*+

Open Access
Article

Abstract

The latest LHCb angular analysis of the rare decay BKμ+μ shows some discrepancies from the SM up to the 3.7σ level. There is a consistent new physics explanation of these anomalies, while it is also reasonable that these anomalies are just statistical fluctuations and/or a direct consequence of underestimated hadronic uncertainties. We briefly discuss possible cross-checks of the various hypotheses with an analysis of the inclusive BXs+ based on the data collected by the B factories Babar and Belle and also based on future opportunities at SuperBelle. We also present a global analysis of the latest LHCb data under the hypothesis of Minimal Flavour Violation. The latter is an important benchmark scenario for new physics models. Any measurements beyond the MFV bounds and relations unambiguously indicate the existence of new flavour structures next to the Yukawa couplings of the Standard Model. However, if new physics is responsible for these discrepancies, we show it is compatible with the MFV hypothesis, so no new flavour structures are needed. Moreover, we analyse the impact of the correlations between the observables based on a Monte Carlo study.

Keywords

Rare Decays Beyond Standard Model B-Physics 

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Copyright information

© The Author(s) 2014

Authors and Affiliations

  1. 1.PRISMA Cluster of Excellence and Institute for Physics (THEP)Johannes Gutenberg UniversityMainzGermany
  2. 2.Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPCClermont-FerrandFrance
  3. 3.CERN Theory Division, Physics DepartmentGeneva 23Switzerland

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