Exploring dark matter, neutrino mass, and RK (∗),φ anomalies in Lμ-Lτ model

Abstract

We investigate Majorana dark matter in a new variant of U(1)Lμ-Lτ gauge extension of the Standard Model, where the scalar sector is enriched with an inert doublet and a (3̄, 1, 1/3) scalar leptoquark. We compute the weakly interacting massive particle-nucleon cross section in the leptoquark portal and the relic density mediated by inert doublet components, the leptoquark, and the new Z′ boson. We constrain the parameter space consistent with the Planck limit on the relic density and the PICO-60 and LUX bounds on the spin-dependent direct detection cross section. Furthermore, we constrain the new couplings from the present experimental data on Br(τ→μντν̄μ), Br(B→Xsγ), Br(B̄0→K̄0μ+μ-), Br(B+→K+τ+τ-), and Bs-Bs̄ mixing, which occur at the one-loop level in the presence of the Z′ and leptoquark. Using the allowed parameter space, we estimate the form-factor-independent P4,5′ observables and the lepton nonuniversality parameters RK, RK∗, and Rφ. We also briefly discuss neutrino mass generation at the one-loop level and the viable parameter region to explain current neutrino oscillation data.