Efficacy of scalar leptoquark on $B_s \to (K^{(*)}, D_s^{(*)}) \tau \bar \nu_\tau$ decay modes

TL;DR

This paper investigates how scalar leptoquarks influence rare $B_s$ meson decays involving tau leptons, constraining new physics parameters and analyzing effects on decay observables and lepton universality.

Contribution

It provides a comprehensive analysis of scalar leptoquark effects on $B_s$ decay modes, including parameter constraints and predictions for various observables.

Findings

Scalar leptoquarks can significantly alter decay branching ratios.

Lepton non-universality may be observable in these decay modes.

Constraints on leptoquark parameters are consistent with current experimental limits.

Abstract

We scrutinize the impact of various relevant scalar leptoquarks on the physical observables associated with the rare semileptonic decay processes of $B_s$ meson involving $b \to (u, c) l\bar \nu_l$ quark level transitions. We constrain the new parameter space consistent with the experimental limit on Br($B_{u,c} \to \tau \nu_l$), Br($B \to \pi \tau \bar \nu_\tau$), $R_{D^{(*)}}, R_{J/\psi}$ and $R_\pi^l$ observables. Using the allowed parameter space, we compute the branching ratios, forward-backward asymmetries, lepton and hardon polarization asymmetries of $B_s \to (K^{(*)}, D_s^{(*)}) \tau \bar \nu_\tau$ decay modes. Forbye, we look at the possibility of existence of lepton non-universality in these processes.