Vector leptoquark resolution of RK and RD(⁎) puzzles

Abstract

We propose that three recent anomalies in B meson decays, RD(⁎), RK, and P5′, might be explained by only one vector leptoquark weak triplet state. The constraints on the parameter space are obtained by considering t→bτ+ν data, lepton flavor universality tests in the kaon sector, bounds on the lepton flavor violating decay B→Kμτ, and b→cμ−ν¯ decays. The presence of such vector leptoquark could be exposed in precise measurements of top semitauonic decays to b quark. The model predicts enhanced decay rate of B→Kν¯ν, approximate equality of lepton flavor universality ratios RK⁎, RK, and suppressed branching fraction of Bs→μ+μ−.