Analysis of the $\Lambda_{b}\rar \Lambda \ell^+\ell^- $ decay in QCD

TL;DR

This paper investigates the semileptonic decay of Lambda_b baryons into Lambda baryons and leptons using light cone QCD sum rules, providing form factors, branching ratios, and comparisons with heavy quark effective theory.

Contribution

It constructs sum rules for all twelve form factors of the decay and predicts the branching ratio, highlighting the channel's detectability at LHCb.

Findings

Form factors for Lambda_b to Lambda decay are calculated.

Branching ratio suggests high detectability at LHCb.

Results agree with heavy quark effective theory predictions.

Abstract

Taking into account the $\Lambda$ baryon distribution amplitudes and the most general form of the interpolating current of the $\Lambda_{b}$, the semileptonic $\Lambda_{b}\rar \Lambda \ell^+\ell^- $ transition is investigated in the framework of the light cone QCD sum rules. Sum rules for all twelve form factors responsible for the $\Lambda_{b}\rar \Lambda \ell^+\ell^- $ decay are constructed. The obtained results for the form factors are used to compute the branching fraction. A comparison of the obtained results with the existing predictions of the heavy quark effective theory is presented. The results of the branching ratio shows the detectability of this channel at the LHCb in the near future is quite high.