FCNC $B_s$ and $\Lambda_b$ transitions: Standard Model versus a single Universal Extra Dimension scenario

TL;DR

This paper compares Standard Model predictions with a Universal Extra Dimension scenario for rare B_s and Lambda_b decays, highlighting how future measurements can constrain extra dimensional parameters and improve understanding of hadronic uncertainties.

Contribution

It provides a detailed analysis of FCNC B_s and Lambda_b decays within a Universal Extra Dimension framework, emphasizing potential experimental constraints on the extra dimension radius R.

Findings

Decay rates are within reach of LHCb and other experiments.

Measurements can constrain the extra dimension radius R.

Hadronic uncertainties are discussed and potential improvements are identified.

Abstract

We study the FCNC $B_s \to \phi \gamma, \phi \nu \bar \nu$ and $\Lambda_b \to \Lambda \gamma, \Lambda \nu \bar \nu$ transitions in the Standard Model and in a scenario with a single Universal Extra Dimension. In particular, we focus on the present knowledge of the hadronic uncertainties and on possible improvements. We discuss how the measurements of these modes can be used to constrain the new parameter involved in the extra dimensional scenario, the radius $R$ of the extra dimension, completing the information available from B-factories. The rates of these $b \to s$ induced decays are within the reach of new experiments, such as LHCb.