Double-Lepton Polarization Asymmetries and Branching Ratio of the $B\rar \gamma l^+ l^- $ transition in Universal Extra Dimension

TL;DR

This paper investigates how the presence of a universal extra dimension affects the branching ratio and lepton polarization asymmetries in the radiative dileptonic B meson decay, comparing results with the standard model.

Contribution

It provides a detailed analysis of the impact of universal extra dimensions on B meson decay observables using light cone QCD sum rules, highlighting deviations from the standard model at certain parameters.

Findings

Deviations from the standard model predictions at lower compactification scales.

Enhanced sensitivity of polarization asymmetries to extra dimension effects.

Quantitative estimates of branching ratio modifications due to extra dimensions.

Abstract

We study the radiative dileptonic $B \rar \gamma l^+ l^- $ transition in the presence of a universal extra dimension in the Applequist-Cheng-Dobrescu model. In particular, using the corresponding form factors calculated via light cone QCD sum rules, we analyze the branching ratio and double lepton polarization asymmetries related to this channel and compare the results with the predictions of the standard model. We show how the results deviate from predictions of the standard model at lower values of the compactification factor ($1/R $) of extra dimension.