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تسجيل مستخدم جديدLepton number violating operators with standard model gauge fields: A survey of neutrino masses from 3-loops and their link to dark matter
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We investigate neutrino mass generation scenarios where the lepton number breaking new physics couples only to the Standard Model (SM) right-handed charged lepton chirality. The lowest-order lepton number violating effective operator which describes this framework is a unique dimension nine operator involving SM gauge fields, $mathcal{O}_9$. We find that there are two possible classes of new physics scenarios giving rise to this $mathcal{O}_9$ operator. In these scenarios neutrino masses are induced radiatively via dark matter interactions, linking the dark matter to a natural explanation for the smallness of neutrino masses compared to the electroweak scale. We discuss the phenomenology and existing constraints in the different neutrino mass models within each class. In particular, we analyze the important interplay between neutrino mixing and neutrinoless double $beta$-decay in order to predict characteristic signatures and disfavour certain scenarios.
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