Octant of 𝜃23, MH, 0νββ decay and vacuum alignment of A4 flavor symmetry in an inverse seesaw model

Abstract

Measurements of disappearance channel of long baseline accelerator-based experiments (like NO[Formula: see text]A) are inflicted with the problem of octant degeneracy. In these experiments, the mass hierarchy (MH) sensitivity depends upon the value of CP-violating phase [Formula: see text]. Moreover, MH of light neutrino masses is still not fixed. Also, the flavor structure of fermions is yet not fully understood. We discuss all these issues in a highly predictive, low-scale inverse seesaw (ISS) model within the framework of [Formula: see text] flavor symmetry. Recent global analysis has shown a preference for normal hierarchy and higher octant of [Formula: see text], and hence we discuss our results with reference to these, and find that the vacuum alignment of [Formula: see text] triplet flavon [Formula: see text] favors these results. Finally, we check if our very precise prediction on [Formula: see text] and the lightest neutrino mass falls within the range of sensitivities of the neutrinoless double beta decay [Formula: see text] experiments. We note that when octant of [Formula: see text] and MH is fixed by more precise measurements of future experiments, then through our results, it would be possible to precisely identify the favorable vacuum alignment corresponding to the [Formula: see text] triplet field as predicted in our model.