Journal of High Energy Physics

, 2014:53 | Cite as

Global fits to b → sℓℓ data and signs for lepton non-universality

Open Access
Regular Article - Theoretical Physics

Abstract

There are some slight tensions with the SM predictions within the latest LHCb measurements. Besides the known anomaly in one angular observable of the rare decay BK*μ+μ, another small discrepancy recently occurred. The ratio RK = BR(B+K+μ+μ)/BR(B+K+e+e) in the low-q2 region has been measured by LHCb showing a 2.6σ deviation from the SM prediction. In contrast to the anomaly in the rare decay BK*μ+μ which is affected by power corrections, the ratio RK is theoretically rather clean. We analyse all the bsℓℓ data with global fits and in particular explore the possibility of breaking of lepton universality. Possible cross-checks with an analysis of the inclusive BXs+ decay are also explored.

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.Université de Lyon, Université Lyon 1, Centre de Recherche Astrophysique de Lyon, CNRS, UMR 5574Saint-Genis Laval cedexFrance
  3. 3.Ecole Normale Supérieure de LyonLyonFrance
  4. 4.CERN Theory Division, Physics DepartmentGeneva 23Switzerland
  5. 5.Institut Universitaire de FranceParisFrance
  6. 6.School of Particles and AcceleratorsInstitute for Research in Fundamental Sciences (IPM)TehranIran

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