Octant of ${\theta }_{23}$, MH, $0\nu \beta \beta$ decay and vacuum alignment of $A_4$ flavour symmetry in an inverse seesaw model

Abstract

Measurements of disappearance channel of long baseline accelerator based experiments (like NO$\nu$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 ${\delta }_{CP}$. Moreover, MH of light neutrino masses is still not fixed. Also, the flavour 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 $A_4$ flavour symmetry. Recent global analysis has shown a preference for normal hierarchy and higher octant of ${\theta }_{23}$, and hence we discuss our results with reference to these, and find that the vacuum alignment of $A_4$ triplet flavon (1,-1,-1) favours these results. Finally, we check if our very precise prediction on $m_{ee}$ and the lightest neutrino mass falls within the range of sensitivities of the neutrinoless double beta decay ($0\nu \beta \beta$) experiments. We note that when octant of ${\theta }_{23}$ and MH is fixed by more precise measurements of future experiments, then through our results, it would be possible to precisely identify the favourable vacuum alignment corresponding to the $A_4$ triplet field as predicted in our model.

24 pages, 5 figures

References in corpus (11)

• Indication of Electron Neutrino Appearance from an Accelerator-produced Off-axis Muon Neutrino Beam
• 2020 Global reassessment of the neutrino oscillation picture
• Neutrinoless Double-Beta Decay: a Probe of Physics Beyond the Standard Model
• Measurement of Atmospheric Tau Neutrino Appearance with IceCube DeepCore
• CP-Violating Neutrino Non-Standard Interactions in Long-Baseline-Accelerator Data
• New expectations and uncertainties on neutrinoless double beta decay
• Back to (Mass-)Square(d) One: The Neutrino Mass Ordering in Light of Recent Data
• Compatibility of theta13 and the Type I Seesaw Model with A4 Symmetry
• Determining the Octant of ${\theta }_{23}$ at LBNE in conjunction with Reactor Experiments
• Physics potentials with a combined sensitivity of T2K-II, NO$\nu$A extension and JUNO
• Impact of high energy beam tunes on the sensitivities to the standard unknowns at DUNE

Cited by in corpus (1)

• Exploring the feasibility of the charged lepton flavor violating decay $\mu \to e+\gamma$ in inverse and linear seesaw mechanisms with $A_4$ flavour symmetry