Muon (g − 2) and flavor puzzles in the U(1)X-gauged leptoquark model

Abstract

We present an economical model where an S1 leptoquark and an anomaly-free U(1)X gauge symmetry with X = B3− 2Lμ/3 − Lτ/3 are introduced, to account for the muon anomalous magnetic moment aμ≡ (gμ− 2) and flavor puzzles including {R}_{K^{left(ast right)}} and {R}_{D^{left(ast right)}} anomalies together with quark and lepton flavor mixing. The Z′ gauge boson associated with the U(1)X symmetry is responsible for the {R}_{K^{left(ast right)}} anomaly. Meanwhile, the specific flavor mixing patterns of quarks and leptons can be generated after the spontaneous breakdown of the U(1)X gauge symmetry via the Froggatt-Nielsen mechanism. The S1 leptoquark which is also charged under the U(1)X gauge symmetry can simultaneously explain the latest muon (g − 2) result and the {R}_{D^{left(ast right)}} anomaly. In addition, we also discuss several other experimental constraints on our model.