Effects of scalar leptoquark on semileptonic $\Lambda_b$ decays

We study the scalar leptoquark effects on the rare semileptonic decays of $\Lambda_b$ baryon, governed by the quark level transition $b \to s l^+ l^-$. We estimate the branching ratios, forward-backward asymmetries, lepton polarization parameters and the lepton flavour non-universality effects in these decay channels. We find significant deviations from the corresponding standard model predictions in some of the observables due to leptoquark effects. We also investigate the lepton flavour violating decays $\Lambda_b \to \Lambda l_i^- l_j^+$, the branching ratios of which are found to be ${\cal O}(10^{-10} - 10^{-9})$.