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We investigate low-scale resonant leptogenesis in an SU(5)×T13 model where a single high-energy phase in the complex tribimaximal seesaw mixing produces the yet to be observed low-energy Dirac and Majorana CP phases. A fourth right-handed neutrino, required to generate viable light neutrino masses within this scenario, also turns out to be necessary for successful resonant leptogenesis where CP asymmetry is produced by the same high-energy phase. We derive a lower bound on the right-handed neutrino mass spectrum in the GeV range, where part of the parameter space, although in tension with big bang nucleosynthesis constraints, can be probed in planned high-intensity experiments like DUNE. We also find the existence of a curious upper bound (TeV-scale) on the right-handed neutrino mass spectrum in majority of the parameter space due to significant washout of the resonant asymmetry by lighter right-handed neutrinos. While in most of the parameter space of our model classical Boltzmann equations are sufficient, when right-handed neutrino masses are below the electroweak sphalerons freeze-out temperature we resort to the more general density matrix formalism to take into account decays and oscillations of the right-handed neutrinos as well as their helicities which are relevant when they are relativistic. [ABSTRACT FROM AUTHOR]

We investigate nonresonant thermal leptogenesis in the context of the SU(5)×T13 "asymmetric texture", where both Dirac and Majorana CP violation arise from a single phase in the tribimaximal seesaw mixing matrix. We show that the baryon asymmetry of the universe can be explained in this model only when flavor effects are considered for right-handed neutrino masses of O(1011-1012)  GeV. The sign of the baryon asymmetry also determines the sign of the previouslyWe investigate nonresonant thermal leptogenesis in the context of the SU(5)×T13 "asymmetric texture", where both Dirac and Majorana CP violation arise from a single phase in the tribimaximal seesaw mixing matrix. We show that the baryon asymmetry of the universe can be explained in this model only when flavor effects are considered for right-handed neutrino masses of O(1011-1012)  GeV. The sign of the baryon asymmetry also determines the sign of the previously predicted Dirac CP phase |δCP|=1.32π, consistent with the latest global fit δCPPDG=1.37±0.17π. [ABSTRACT FROM AUTHOR]

We extend the recently proposed SU(5)×T13 model for the asymmetric texture to the up-type quark and seesaw sectors. The hierarchical up-type quark masses are generated from higher-dimensional operators involving family-singlet Higgses, gauge-singlet familons, and vectorlike messengers. The complex-tribimaximal seesaw mixing arises from the vacuum structure of a minimal number of familons, resulting in an alignment between the Yukawa and Majorana matrices of the seesaw formula. Introducing four right-handed neutrinos, normal ordering of the light neutrino masses is obtained, with mν1=27.6  meV, mν2=28.9  meV and mν3=57.8  meV. Their sum almost saturates Planck's cosmological upper bound (120 meV). The right-handed neutrino masses are expressed in terms of two parameters for a particular choice of familon vacuum alignment. We predict the CP Jarlskog-Greenberg invariant to be |J|=0.028, consistent with the current Particle Data Group (PDG) estimate, and Majorana invariants |I1|=0.106 and |I2|=0.011. A sign ambiguity in the model parameters leads to two possibilities for the invariant mass parameter |mββ|: 13.02 or 25.21 meV, both within an order of magnitude of the most rigorous experimental upper limit (61-165 meV). [ABSTRACT FROM AUTHOR]