Electron $g-2$ corrections from axion dark matter

TL;DR

This paper investigates how a local axion dark matter background influences the electron's anomalous magnetic moment, providing new constraints on axion-electron interactions for ultra-light axions.

Contribution

It offers the first analytical calculation of axion-induced loop corrections to the electron g-2 and derives the strongest existing constraints for very low-mass axions.

Findings

Placed new upper bounds on axion-electron coupling for axion masses below 3×10^{-18} eV.

Derived analytical formulas for spin and cyclotron frequencies in the presence of axion dark matter.

Showed that current measurements significantly constrain ultra-light axion models.

Abstract

We consider the effects of a local axion dark matter background on the $g-2$ of the electron. We calculate loop corrections to the photon-electron vertex and determine analytical formulas for the spin and cyclotron frequencies when the electron is in an external magnetic field. By comparing with current measurements of these observables, we are able to place the strongest constraint on the axion-elecron coupling for axion masses below $3\times10^{-18}\text{eV}$.