Mrinal Kumar Das

Discriminating neutrino mass models using Type-II see-saw formula

An attempt has been made to discriminate theoretically the three possible patterns of neutrino mass models,viz., degenerate, inverted hierarchical and normal hierachical models, within the framework of Type-II see-saw formula. From detailed numerical analysis we are able to arrive at a conclusion that the inverted hierarchical model with the same CP phase (referred to as Type [IIA]), appears to be most favourable to survive in nature (and hence most stable), with the normal hierarchical model (Type [III]) and inverted hierarchical model with opposite CP phase (Type [IIB]), follow next. The degenerate models (Types [IA,IB,IC]) are found to be most unstable. The neutrino mass matrices which are obtained using the usual canonical see-saw formula (Type I), and which also give almost good predictions of neutrino masses and mixings consistent with the latest neutrino oscillation data, are re-examined in the presence of the left-handed Higgs triplet within the framework of non-canonical see-saw formula (Type II). We then estimate a parameter (the so-called discriminator) which may represent the minimum degree of suppression of the extra term arising from the presence of left-handed Higgs triplet, so as to restore the good predictions on neutrino masses and mixings already acquired in Type-I see-saw model. The neutrino mass model is said to be favourable and hence stable when its canonical see-saw term dominates over the non-canonical (perturbative) term, and this condition is used here as a criterion for discriminating neutrino mass models.

Perturbations to theμ−τsymmetry, leptogenesis, and lepton flavor violation with the type II seesaw mechanism

We study the possibility of generating non-zero reactor mixing angle

Numerical consistency check between two approaches to radiative corrections for neutrino masses and mixings

theta_{13}

Neutrino masses and mixings with non-zero θ13 in type I + II seesaw models

by perturbing the

Discriminating Majorana neutrino textures in light of the baryon asymmetry

mu-tau

Quasi-Degenerate Neutrinos in Type II Seesaw Models

symmetric neutrino mass matrix. The leading order

Common Origin of Non-zero

mu-tau

\theta_{13}

symmetric neutrino mass matrix originates from type I seesaw mechanism whereas the perturbations to

and Dark Matter in an

mu-tau

S_4

symmetry originate from type II seesaw term. We consider four different realizations of