English

Hint of Lepton Flavour Non-Universality in $B$ Meson Decays

High Energy Physics - Phenomenology 2015-06-22 v3 High Energy Physics - Experiment

Abstract

The LHCb collaboration has recently presented their result on R_K = BR(B+ -> K+ mu+ mu-)/ BR(B+ -> K+ e+ e-) for the dilepton invariant mass bin m_{ll}^2 = 1-6 GeV^2 (l = mu, e). The measurement shows an intriguing 2.6 sigma deviation from the Standard Model (SM) prediction. In view of this, we study model independent New Physics (NP) explanations of R_K consistent with other measurements involving b -> s l l transition, relaxing the assumption of lepton universality. We perform a Bayesian statistical fit to the NP Wilson Coefficients and compare the Bayes Factors of the different hypotheses in order to quantify their goodness-of-fit. We show that the data slightly favours NP in the muon sector over NP in the electron sector.

Keywords

Cite

@article{arxiv.1408.4097,
  title  = {Hint of Lepton Flavour Non-Universality in $B$ Meson Decays},
  author = {Diptimoy Ghosh and Marco Nardecchia and S. A. Renner},
  journal= {arXiv preprint arXiv:1408.4097},
  year   = {2015}
}

Comments

Final version, to appear in JHEP