Analysis of ${\Lambda}_b\rightarrow{\Lambda}l^+ l^-$ rare decays in a non-universal $Z'$ model

TL;DR

This paper studies rare baryonic decays involving Lambda_b particles within a non-universal Z' model, analyzing various asymmetries and decay rates to identify potential deviations from the Standard Model that suggest new physics.

Contribution

It introduces an analysis of Lambda_b to Lambda l+ l- decays considering Z'-mediated FCNCs, highlighting significant deviations from SM predictions as potential signals of new physics.

Findings

Significant deviations from SM in decay rates and asymmetries.

Potential indication of new physics from Z' gauge boson effects.

Enhanced sensitivity of observables to Z' contributions.

Abstract

We investigate the rare baryonic ${\Lambda}_b\rightarrow{\Lambda}l^+ l^-$ decays in a non-universal $Z'$ model, which is one of the well-motivated extensions of the standard model (SM). Considering the effects of $Z'$-mediated flavour-changing neutral currents (FCNCs) we analyse the differential decay rate, forward-backward asymmetries and lepton polarisation asymmetries for the ${\Lambda}_b\rightarrow{\Lambda}l^+ l^-$ decays. We find significant deviations from their SM predictions, which could indicate new physics arising from the $Z'$ gauge boson.