The Ellipse of Muon Dipole Moments

TL;DR

This paper demonstrates that new physics affecting the muon magnetic moment also impacts Higgs decay to muons and the muon electric dipole moment, forming a correlated 'ellipse' that can be tested with future experiments.

Contribution

It establishes a geometric relationship between muon dipole moments and Higgs decay rates, providing a novel way to test models explaining the muon g-2 anomaly.

Findings

Future Higgs decay measurements will constrain muon dipole moments.

Electric dipole moment measurements will test many models for muon g-2.

The three observables are strongly correlated in models with chirally-enhanced contributions.

Abstract

We show that any new interaction resulting in a chirally-enhanced contribution to the muon magnetic moment necessarily modifies the decay rate of the Higgs boson to muon pairs or generates the muon electric dipole moment. These three observables are highly correlated, and near future measurements of $h\to \mu^+\mu^-$ will carve an ellipse in the plane of dipole moments for any such model. Together with the future measurements of the electric dipole moment many models able to explain the muon g-2 anomaly can be efficiently tested.