$U(1)_\chi$ and Seesaw Dirac Neutrinos

Abstract

In the context of $SO(10) \to SU(5)\times U(1)\chi$, it is shown how seesaw Dirac neutrinos may be obtained. In this framework, $U(1)$ lepton number is conserved, with which self-interacting dark matter with a light scalar dilepton mediator may be implemented. In addition, $U(1)$ baryon number may be broken to (−1)3B, thereby generating a baryonasymmetry of the Universe. The axionic solution to the strong CP problem may alsobe incorporated.