A bstract We investigate a radiative seesaw model with two leptoquarks under non-holomorphic modular A 4 symmetry. The leptons and quarks belong to non-trivial representations of the modular A 4 and the structures of their mass matrices are restricted. Neutrino masses are generated at one-loop level via leptoquark inside loop diagram where structures of relevant Yukawa interactions are determined by the modular A 4 symmetry. We scan the free parameters in the model and try to fit all the observed data for both lepton and quark sectors. For allowed parameters, we show some predictions regarding neutrino observables such as sum of neutrino mass and neutrinoless double beta decay.
Nomura et al. (2025) studied this question.