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

Understand

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.