Searching for New Physics in the Differential Decay Width of a Lambda_b Semi-leptonic Decay

TL;DR

This paper investigates how new physics could influence the differential decay width in the semi-leptonic decay of Lambda_b baryons, proposing measurements to detect potential deviations from the Standard Model.

Contribution

It provides a model-independent expression for the differential decay width and analyzes its sensitivity to various new physics interactions in Lambda_b decays.

Findings

Certain coefficients of the decay width are sensitive to the type of new physics interaction.

Proposed measurements are feasible with current experimental capabilities.

Different new physics scenarios produce distinguishable effects in decay observables.

Abstract

We propose to investigate the effects of new physics in the semi-leptonic sequential decay $\Lambda_b \to \Lambda_c (\to \Lambda \pi) \tau{\bar \nu}_{\tau}$. Firstly, we write the general, model independent, non-covariant expression of the differential decay width of the process. Then, we calculate that observable according to three different types of new physics interactions, which might explain the tension of data with the standard model predictions. We find that some coefficients of the differential decay width are sensitive to the kind of interaction that is assumed. The measurements that we suggest seem to be feasible.