Muon anomalous magnetic moment and penguin loops in warped extra dimensions

TL;DR

This paper calculates the muon anomalous magnetic moment and penguin transitions within a five-dimensional Randall-Sundrum model, providing detailed contributions from gauge-boson and Higgs exchanges, and matching the 5D theory to an extended Standard Model.

Contribution

It introduces a fully five-dimensional framework for computing muon magnetic moments and penguin transitions in warped extra dimension models, including gauge and Higgs contributions.

Findings

Gauge-boson exchange contributes Delta a_mu b1 8.8 (27.2) x 10^{-11} (1 TeV/T)^2.

Higgs-exchange contribution depends on 5D Yukawa structure and Higgs localization.

Results relate the KK mass scale to the muon anomalous magnetic moment.

Abstract

We describe the computation of the one-loop muon anomalous magnetic moment and radiative penguin transitions in the minimal and custodially protected Randall-Sundrum model. A fully five-dimensional (5D) framework is employed to match the 5D theory onto the Standard Model extended by dimension-six operators. The additional contribution to the anomalous magnetic moment from the gauge-boson exchange contributions is Delta a_mu \approx 8.8 (27.2) x 10^(-11) x (1 TeV/T)^2, where the first (second) number refers to the minimal (custodially-protected) model. Here $1/T$ denotes the location of the TeV brane in conformal coordinates, and is related to the mass of the lowest gauge-boson KK excitation by M_KK \approx 2.35 T. We also determine the Higgs-exchange contribution, which depends on the 5D Yukawa structure and the precise interpretation of the localisation of the Higgs field near or at the TeV brane.