Light dark matter, rare $B$ decays with missing energy in $L_{\mu}-L_{\tau}$ model with a scalar leptoquark

TL;DR

This paper explores a $U(1)_{L_-L_ au}$ gauge extension of the Standard Model to explain light dark matter, flavor anomalies, and neutrino masses, analyzing rare B decays with missing energy.

Contribution

It introduces a novel model combining a $U(1)_{L_-L_ au}$ gauge symmetry with scalar leptoquarks and inert scalars, addressing multiple phenomena simultaneously.

Findings

Constraints on model parameters from $b o sll$ and $b o s \gamma$ decays.

Predictions for rare $B$ decay branching ratios with missing energy.

Implications for dark matter relic density and flavor observables.

Abstract

We investigate the phenomenology of light GeV-scale fermionic dark matter in $U(1)_{L_\mu - L_{\tau}}$ gauge extension of the Standard Model. Heavy neutral fermions alongside with a $S_1(\overline{3}$,$1$,$1/3$) scalar leptoquark and an inert scalar doublet are added to address the flavor anomalies and light neutrino mass respectively. The light gauge boson associated with $U(1)_{L_\mu-L_\tau}$ gauge group mediates dark to visible sector and helps to obtain the correct relic density. Aided with a colored scalar, we constrain the new model parameters by using the branching ratios of various $b \to sll$ and $b \to s \gamma$ decay processes as well as the lepton flavour non-universality observables $R_{K^{(*)}}$ and then show the implication on the branching ratios of some rare semileptonic $B \to (K^{(*)}, \phi)+$ missing energy, processes.