Inert charged-Higgs on muon $g-2$ and radiative neutrino mass in a scotogenic model

Abstract

A simple extension of Ma s approach in a scotogenic model is studied for the purpose of simultaneously interpreting the neutrino data and the excess of muon anomalous magnetic moment (muon $g-2$). The feasible minimal extension is to add an $Z_2$-odd vector-like lepton doublet to the Ma s model. It is found that in addition to the neutrino data, the strict constraints on the relevant parameters are from the electroweak oblique parameters and the induced lepton-flavor violation processes, such as $\\ell_i \\to \\ell_j \\gamma$ and $\\ell_i \\to \\ell^-_j \\ell^-_j \\ell^+_j$. Performing parameter scan, we numerically demonstrate that when the constraint conditions are satisfied, the muon $g-2$ of $O(10^{-9})$ can be achieved, where it can be expected that with a $5\\sigma$ observation, the Muon $g-2$ experiment at Fermilab can observe $a_\\mu \\approx 13.31 \\times 10^{-10}$ when the current experiment and the SM errors are reduced by a factor of 4 and 2, respectively. Moreover, the branching ratio of the $\\tau \\to \\mu \\gamma$ decay can match the Belle II sensitivity of $O(10^{-9})$ with an integrated luminosity of 50 ab$^{-1}$.