A Comparative Study of Contributions to $\epsilon_K$ in the RS Model

TL;DR

This paper compares the effects of Higgs and KK gluon contributions to epsilon_K in the RS model, revealing that KK gluons typically impose stronger constraints, but Higgs effects can dominate in some scenarios, with detailed renormalization analysis.

Contribution

It provides a comparative analysis of Higgs and KK gluon contributions to epsilon_K in the RS model, including renormalization procedures and scenario-dependent results.

Findings

KK gluon exchange imposes the strongest constraints for localized Higgs.

Higgs contributions can surpass KK gluon effects in certain bulk Higgs scenarios.

Detailed renormalization procedures are essential for accurate low-energy predictions.

Abstract

We contrast the impact of Higgs mediated flavor changing neutral currents on epsilon_K in the framework of a warped extra dimension that was recently calculated by Azatov et al. with the older results for Kaluza-Klein gluon induced corrections to that observable. We find that the most stringent constraint on the KK scale for a Higgs field localized on the infrared brane for reasonable additional assumptions comes from KK gluon exchange. In the case of a bulk Higgs field we show that for certain scenarios the Higgs contribution can in fact exceed the KK gluon contribution. In the course of this analysis we also describe in detail the different renormalization procedures that have to be employed in the KK gluon and Higgs cases to relate the new physics at high energies to low energy observables.