Construction and phenomenological analysis of dynamical Inverse seesaw neutrino mixing model

Abstract

In this manuscript, a dynamical inverse seesaw neutrino ISS(3+1+1+1) mixing model based on the gauge symmetry $U(1)_{B-L}$ extended by the flavor symmetry $A_{4}\times Z_{2}$ has been constructed. ISS(3+1+1+1) represents three generations of right-handed neutrinos and an extra three generation of singlets sterile neutrinos, wherein the right-handed neutrinos are triplets under $A_4$ symmetry. Furthermore, the five scalar flavon fields are considered in the model, which reproduce neutrino oscillation data within the NuFIT 6.0 experimental range with statistical $\text{|pull|}=0.01 σ$. The neutrino mass hierarchy is obtained by minimizing the dynamical $A_4\times Z_2$ scalar flavon $ϕ_v$ potential. The effective neutrino mass parameter $m_{ββ}$ for the neutrinoless double beta decay $0vββ$ has been charecterised in the manuscript. The effective neutrino mass parameter spans a finite region in the parameter space rather then being confined to a single point and it is constrained by the KamLAND-Zen excluded band. The model successfully explains active-sterile neutrino mixing and non-unitarity of the PMNS matrix is consistent with the cosmological upper bound. The minimum value of the sum of the active neutrinos' mass turns out to be $m_{i}\approx 62\ \ (99.4)\ \text{meV}$ for Normal ordering (Inverted ordering), which lies within the range of both Planck 2018 loose cosmological limit $\sum m_{i}<120\ \text{meV}$ and tighter limit $\sum m_{i}<72\ \text{meV}$ of DESI-2024. Our model immensely favours normal ordering, in agreement with the tighter constraints reported by DESI-2024.