Resonant leptogenesis and TM$$_1$$ mixing in minimal type-I seesaw model with S$$_4$$ symmetry

Abstract

We present an S$$_4$$ 4 flavour symmetric model within a minimal seesaw framework resulting in mass matrices that leads to TM$$_1$$ 1 mixing. Minimal seesaw is realized by adding two right-handed neutrinos to the Standard Model. The model predicts Normal Hierarchy (NH) for neutrino masses. Using the constrained six-dimensional parameter space of the model, we have evaluated the effective Majorana neutrino mass, which is the parameter of interest in neutrinoless double beta decay experiments. The possibility of explaining baryogenesis via resonant leptogenesis is also examined within the model. A non-zero, resonantly enhanced CP asymmetry generated from the decay of right-handed neutrinos at the TeV scale is studied, considering flavour effects. The evolution of lepton asymmetry is discussed by solving the set of Boltzmann equations numerically and obtain the value of baryon asymmetry to be $$|\eta _B| = 6.3 \times 10^{-10}$$ | η B | = 6.3 × 10 - 10 with the choice of right-handed neutrino mass, $$M_1 = 10$$ M 1 = 10 TeV and mass splitting, $$d \simeq 10^{-8}$$ d ≃ 10 - 8 .

Common origin of θ13 and dark matter within the flavor symmetric scoto-seesaw framework

“…Nevertheless, the TBM mixing scheme can still be considered as a leading-order approximation, requiring adjustments such as accounting for non-zero θ 13 and the Dirac CP phase δ. Possible simple deviations from the TBM mixing are called trimaximal (TM 1 and TM 2 ) mixings where the first and second columns of the TBM mixing respectively remain identical [33][34][35][36][37][38][39][40][41]. Such deviations can be elegantly achieved by considering larger residual symmetry (compared to the TBM scenario) or introducing an additional constituent that breaks the TBM structure [40][41][42][43][44][45][46][47][48][49].…”

“…Possible simple deviations from the TBM mixing are called trimaximal (TM 1 and TM 2 ) mixings where the first and second columns of the TBM mixing respectively remain identical [33][34][35][36][37][38][39][40][41]. Such deviations can be elegantly achieved by considering larger residual symmetry (compared to the TBM scenario) or introducing an additional constituent that breaks the TBM structure [40][41][42][43][44][45][46][47][48][49]. Although the 3σ allowed ranges for all three mixing angles can be explained by both TM 1 and TM 2 mixings, the allowed value of the solar mixing angle θ 12 (within these trimaximal scenarios) slightly prefers the TM 1 over the TM 2 mixing scheme.…”

Non-zero $θ_{13}$, CP-violation and Neutrinoless Double Beta Decay for Neutrino Mixing in the $A_4\times Z_2\times Z_2^\prime$ Flavor Symmetry Model

“…Tri-bimaximal (TBM) [33,34],Trimaximal (TM1/TM2) [35][36][37], Quasi-degenerate neutrino mass models [38] and Bi-large mixing patterns [39][40][41] are examples of phenomenological neutrino mixing patterns. And also various models based on non-abelian discrete flavor symmetries [42] like A 4 [43][44][45], S 3 [46], S 4 [47][48][49], ∆ 27 [50][51][52], ∆ 54 [53,54] [64] adding extra flavons.…”