Leptophilic U(1) Massive Vector Bosons from Large Extra Dimensions

TL;DR

This paper proposes that large extra dimensions and low-scale gravity can explain the muon g-2 anomaly via Kaluza-Klein excitations of a leptophilic U(1) gauge boson, predicting detectable signals in future experiments.

Contribution

It introduces a model where KK excitations of a leptophilic U(1) gauge boson account for the muon g-2 discrepancy, avoiding LHC constraints and linking the effect to the string scale.

Findings

KK excitations can explain the muon g-2 anomaly.

The KK contribution is universal and depends on the string scale.

Future muon experiments can detect the predicted KK signals.

Abstract

We demonstrate that the discrepancy between the anomalous magnetic moment measured at BNL and Fermilab and the Standard Model prediction could be explained within the context of low-scale gravity and large extra-dimensions. The dominant contribution to $(g-2)_\mu$ originates in Kaluza-Klein (KK) excitations (of the lepton gauge boson) which do not mix with quarks (to lowest order) and therefore can be quite light avoiding LHC constraints. We show that the KK contribution to $(g-2)_\mu$ is universal with the string scale entering as an effective cutoff. The KK tower provides a unequivocal distinctive signal which will be within reach of the future muon smasher.