Impact of vector leptoquark on $\bar B \to \bar K^* l^+ l^-$ anomalies

TL;DR

This paper explores how vector leptoquarks could explain anomalies in B meson decays related to lepton flavor universality violation, providing predictions for various observables and constraints from related processes.

Contribution

It introduces a comprehensive analysis of vector leptoquark effects on B decay anomalies, including constraints from other decays and predictions for multiple observables.

Findings

Constraints on leptoquark couplings from B and K decay data

Predictions for branching ratios and asymmetries in B decays

Potential signals of lepton flavor violation in K decays

Abstract

Motivated by the recent measurement of the lepton flavour nonuniversality ratio $R_{K^*}$ by the LHCb Collaboration, we study the implications of vector leptoquarks on the observed anomalies associated with the $\bar B \to \bar K^* l^+ l^-$ decay processes. The leptoquark couplings are constrained from the measured branching ratios of $B_s \to l^+ l^-$, $K_L \to l^+ l^-$ and $B_s \to \mu^\mp e^\pm$ processes. Using these constrained couplings, we estimate the branching ratios, forward-backward and lepton polarization asymmetries and also the form factor independent optimized observables ($P_{i}^{(\prime)}$) for $\bar B \to \bar K^* l^+ l^-$ modes in the high recoil limit. We also study the other lepton flavour universality violating observables, such as $Q_{F_{L, T}}$, $Q_{i}$ and $B_{5, 6s}$, where $i=1,2,\cdots6, 8$. Furthermore, we investigate the lepton flavour violating $K_L \to \mu^\mp e^\pm$ decay process in this model.