TeV Scale Resonant Leptogenesis with $L_{\mu}-L_{\tau}$ Gauge Symmetry in the Light of Muon $(g-2)$

TL;DR

This paper explores a gauged $L_{}-L_{}$ model to simultaneously explain the muon $(g-2)$ anomaly and baryon asymmetry via resonant leptogenesis, proposing extensions to reconcile experimental constraints.

Contribution

It introduces an extended $L_{}-L_{}$ model with additional Higgs doublets to achieve consistent leptogenesis and muon $(g-2)$ explanations within experimental bounds.

Findings

TeV scale resonant leptogenesis compatible with neutrino data.

Light $L_{}-L_{}$ gauge boson constraints from experiments.

Extended model with two Higgs doublets enables successful leptogenesis and muon $(g-2)$ fit.

Abstract

Motivated by the growing evidence for the possible lepton flavour universality violation after the first results from Fermilab's muon $(g-2)$ measurement, we revisit one of the most widely studied anomaly free extensions of the standard model namely, gauged $L_{\mu}-L_{\tau}$ model, to find a common explanation for muon $(g-2)$ as well as baryon asymmetry of the universe via leptogenesis. The minimal setup allows TeV scale resonant leptogenesis satisfying light neutrino data while the existence of light $L_{\mu}-L_{\tau}$ gauge boson affects the scale of leptogenesis as the right handed neutrinos are charged under it. For $L_{\mu}-L_{\tau}$ gauge boson mass at GeV scale or above, the muon $(g-2)$ favoured parameter space is already ruled out by other experimental data while bringing down its mass to sub-GeV regime leads to vanishing lepton asymmetry due to highly restrictive structures of lepton mass matrices at the scale of leptogenesis. Extending the minimal model with two additional Higgs doublets can lead to a scenario consistent with successful resonant leptogenesis and muon $(g-2)$ while satisfying all relevant experimental data.