An SO(10) times SO(10)' model for common origin of neutrino masses, ordinary and dark matter-antimatter asymmetries

We propose an SO(10) \times SO(10)' model to simultaneously realize a seesaw for Dirac neutrino masses and a leptogenesis for ordinary and dark matter-antimatter asymmetries. A (16\times \overline{16}')_H scalar crossing the SO(10) and SO(10)' sectors plays an essential role in this seesaw-leptogenesis scenario. As a result of lepton number conservation, the lightest dark nucleon as the dark matter particle should have a determined mass around 15 GeV to explain the comparable fractions of ordinary and dark matter in the present universe. The (16\times \overline{16}')_H scalar also mediates a U(1)_{em} \times U(1)'_{em} kinetic mixing after the ordinary and dark left-right symmetry breaking so that we can expect a dark nucleon scattering in direct detection experiments and/or a dark nucleon decay in indirect detection experiments. If a proper mirror symmetry is imposed, our Dirac seesaw will not require more unknown parameters than the canonical Majorana seesaw.