Investigation of the $\Lambda_b \rightarrow \Lambda \ell^+ \ell^-$ transition in universal extra dimension using form factors from full QCD

TL;DR

This paper analyzes the $\,\Lambda_b \rightarrow \Lambda \ell^+ \ell^-$ decay within the universal extra dimension model, examining how observables depend on the compactification radius and comparing with Standard Model predictions.

Contribution

It provides a comprehensive analysis of the decay process using full QCD form factors in the universal extra dimension model, highlighting the sensitivity of observables to the extra dimension parameter.

Findings

Observables are sensitive to the compactification radius up to 1000 GeV.

Results differ from Standard Model predictions and heavy quark effective theory.

The study offers potential signals for extra dimensions in baryonic decay processes.

Abstract

Using the related form factors from full QCD which recently are available, we provide a comprehensive analysis of the $\Lambda_b \rightarrow \Lambda \ell^+ \ell^-$ transition in universal extra dimension model in the presence of a single universal extra dimension called the Applequist-Cheng-Dobrescu model. In particular, we analyze some related observables like branching ratio, forward-backward asymmetry, double lepton polarization asymmetries and polarization of the $\Lambda$ baryon in terms of compactification radius and corresponding form factors. We present the sensitivity of these observables to the compactification parameter, 1/R up to 1/R=1000 GeV. We also compare the results with those obtained using the form factors from heavy quark effective theory as well as the SM predictions.