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The minimal seesaw framework, embroiling the Dirac neutrino mass matrix M D and the Majorana neutrino mass matrix M R , is quite successful to explain the current global-fit results of neutrino oscillation data. In this context, we consider the most predictive forms of M D and M R with two simple parameters, respectively. Considering these matrices, we obtain the low-energy neutrino mass matrix under type-I seesaw formalism which obeys μ − τ reflection symmetry and predicts 𝜃 2 3 = π / 4 and δ = ± π / 2. In the given set-up, we also evaluate the Baryon Asymmetry of the Universe (BAU) through successful leptogenesis and find that perturbation of 𝒪 (1 0 − 2) leads to the observed BAU and breaks exactness of the symmetry. Moreover, we also perform various correlation studies among different parameters in the framework of broken symmetry. [ABSTRACT FROM AUTHOR]

Bi-large patterns for the leptonic mixing matrix are confronted with current neutrino oscillation data. We analyse the status of these patterns and determine, through realistic simulations, the potential of the upcoming long-baseline experiment DUNE in testing bi-large ansatze and discriminating amongst them. [ABSTRACT FROM AUTHOR]

The octant of the leptonic mixing angle θ 23 and the CP phase δ C P are the two major unknowns (apart from neutrino mass hierarchy) in neutrino oscillation physics. It is well known that the precise determination of octant and δ C P is interlinked through the octant- δ C P degeneracy. In this paper we study the proficiency of the DUNE experiment to determine these parameters scrutinizing, in particular, the role played by the antineutrinos, the broadband nature of the beam and the matter effect. It is well known that for P μ e and P μ ¯ e ¯ the octant- δ C P degeneracy occurs at different values of δ C P , combination of neutrino and antineutrino runs help to resolve this. However, in regions where neutrinos do not have octant degeneracy adding antineutrino data is expected to decrease the sensitivity because of the degeneracy and reduced statistics. However we find that in case of DUNE baseline, the antineutrino runs help even in parameter space where the antineutrino probabilities suffer from degeneracies. We explore this point in detail and point out that this happens because of the (i) broad-band nature of the beam so that even if there is degeneracy at a particular energy bin, over the whole spectrum the degeneracy may not be there; (ii) the enhanced matter effect due to the comparatively longer baseline which creates an increased tension between the neutrino and the antineutrino probabilities which raises the overall χ 2 in case of combined runs. This feature is more prominent for IH since the antineutrino probabilities in this case are much higher than the neutrino probabilities due to matter effects. The main role of antineutrinos in enhancing CP sensitivity is their ability to remove the octant- δ C P degeneracy. However even if one assumes octant to be known the addition of antineutrinos can give enhanced CP sensitivity in some parameter regions due to the tension between the neutrino and antineutrino χ 2 s. [ABSTRACT FROM AUTHOR]

We present a detailed analysis and phenomenological consequences of neutrino mass matrix, , with one-zero texture in the flavor basis where the active neutrino sector is extended by one sterile neutrino (3+1 case). In particular, our aim is to explore behavior of the sterile mixing parameters in detail when one of the elements of the neutrino mass matrix goes to zero. To study this, we consider two distinct mass spectrum of the active neutrinos: (i) completely hierarchical mass spectrum with a vanishing neutrino mass and (ii) completely quasidegenerate mass spectrum. In 3+1 scenario, the low energy neutrino mass matrix, , is a matrix and has 10 independent elements. Thus it can have 10 possible one-zero textures. From the earlier studies it can be inferred that, if one assumes one vanishing neutrino mass, then only seven of these are phenomenologically allowed by the current neutrino oscillation data. On the other hand, if the neutrinos are quasidegenerate then there are eight phenomenologically viable one-zero textures. In this paper, we study the correlations between the sterile mixing parameters for each of these allowed textures for both mass spectrum and also their implications on the effective Majorana mass. [ABSTRACT FROM AUTHOR]

We make an attempt to study the present status of the tetra-maximal neutrino mixing (TMM) pattern. It predicts all the three leptonic mixing angles θ 13 ≈ 8.4 ∘ , θ 12 ≈ 30.4 ∘ , and θ 23 = 45 ∘ together with the three CP-violating phases − δ = ρ = σ = 90 ∘. However, the latest global analysis of neutrino oscillation data prefer relatively higher best-fit value of θ 12 as well as non-maximal values of both θ 23 , δ. In order to explain the realistic data, we study the breaking of TMM pattern. We first examine the breaking of TMM due to renormalization group (RG) running effects and then study the impact of explicit breaking terms. We also examine the effect of RG-induced symmetry breaking on the effective Majorana neutrino mass in neutrinoless double beta decay experiments. [ABSTRACT FROM AUTHOR]