Exploring the feasibility of the charged lepton flavor violating decay μ → e + γ in inverse and linear seesaw mechanisms with A4 flavor symmetry

Abstract

One of the possible ways to explain the observed flavor structure of fundamental particles is to include flavor symmetries in the theories. In this work, we investigate the rare charged lepton flavor violating (cLFV) decay process [Formula: see text] in two of the low-scale ([Formula: see text][Formula: see text]TeV) seesaw models: (i) the Inverse seesaw (ISS) and (ii) Linear seesaw (LSS) models within the framework of [Formula: see text] flavor symmetry. Apart from the [Formula: see text] flavor symmetry, some other symmetries like [Formula: see text], [Formula: see text] and [Formula: see text] are included to construct the Lagrangian. We use results from our previous work [M. R. Devi and K. Bora, A comparative study of type-II, inverse and linear seesaw mechanisms with [Formula: see text] flavor symmetry, presented at DAE HEP Symp., 2020, Jatni, Odisha; M. R. Devi and K. Bora, Mod. Phys. Lett. A 37, 2250073] where we computed unknown neutrino oscillation parameters within [Formula: see text] limits of their global best fit values, and apply those results to compute the branching ratio (BR) of the muon decay for both the seesaw models. Next we compare our results with the current experimental bounds and sensitivity limits of BR[Formula: see text] as projected by various experiments, and present a comparative analysis that which of the two models is more likely to be tested by which current/future experiment. This is done for various values of currently allowed non-unitarity parameter. This comparative study will help us to pinpoint that which of the low-scale seesaw models and triplet flavon VEV alignments will be more viable and favorable for testing under a common flavor symmetry ([Formula: see text] here), and hence can help discriminate between the two models.