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arXiv · 2108.05907

Anomaly-free Abelian gauge symmetries with Dirac seesaws

Nicolás Bernal·Diego Restrepo
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Abstract

We perform a systematic analysis of Standard Model extensions with an additional anomaly-free gauge $U(1)$ symmetry, to generate tree-level Dirac neutrino masses. An anomaly-free symmetry demands nontrivial conditions on the charges of the unavoidable new states. An intensive scan was performed, looking for solutions generating neutrino masses by the type-I and type-II tree-level Dirac seesaw mechanism, via operators with dimension 5 and 6, that correspond to active or dark symmetries. Special attention was paid to the cases featuring no extra massless chiral fermions or multicomponent dark matter with unconditional stability.

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Nicolás Bernal, Diego Restrepo. 2021-08-12. Anomaly-free Abelian gauge symmetries with Dirac seesaws. https://doi.org/10.1140/epjc%2Fs10052-021-09918-8

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