Dirac Scoto inverse-seesaw from A4 flavor symmetry

Abstract

We present a Dirac scotogenic-like one loop radiative model where the stability of dark matter is intricately linked to the breaking of A4 flavor symmetry. This breaking induces a Z2 dark symmetry, stabilizing the dark matter candidate. The breaking of A4 → Z2 leads to cutting the loop and facilitating a “scoto inverse-seesaw” mass mechanism responsible for neutrino mass generation. This elucidates the explicit explanation of two mass-squared differences, ∆matm2 and ∆msol2 observed in neutrino oscillations. Our model accounts for normal and inverted ordering of neutrino masses, revealing sharp correlations between ∑mi and 〈mβ〉. It also shows strong compatibility with current data in the δCP–θ23 plane. Moreover, stringent constraints on scalar masses narrow down the viable dark matter mass regions, accommodating SU(2)L singlet and doublet scalar dark matter as well as fermionic dark matter. Additionally, our model presents a viable avenue for addressing lepton flavor violating decays while remaining consistent with current experimental constraints. © The Author(s) 2025.