Lepton flavor violation in B decays

Abstract

The Rk measurement by LHCb suggests non-standard lepton non-universality (LNU) to occur in b → sl+l- transitions, with effects in muons rather than electrons. A number of other measurements of b → sl+l- transitions by LHCb and B-factories display disagreement with the Standard-Model predictions and, remarkably, these discrepancies are consistent in magnitude and sign with the Rk effect. Non-standard LNU suggests non-standard lepton flavor violation (LFV) as well. We discuss several B-physics observables to measure such LFV effects.