Semi-secretly interacting ALP as an explanation of Fermilab muon $g-2$ measurement

TL;DR

This paper proposes a novel axion-like particle (ALP) model with vector-like fermions to explain the recent muon g-2 anomaly, extending previous ALP explanations and exploring collider and dark matter implications.

Contribution

It introduces a new ALP-based model with vector-like fermions that better explains the muon g-2 measurement and discusses its collider and dark matter prospects.

Findings

The model fits the muon g-2 anomaly with ALP interactions.

It extends previous ALP explanations by including fermions.

Collider signatures and dark matter viability are analyzed.

Abstract

The muon anomalous magnetic moment measurement has, for more than a decade, been a long-standing anomaly hinting the physics beyond the Standard Model (BSM). The recently announced results from muon $g-2$ collaboration, corresponding to 3.3$\sigma$ deviation from Standard Model value (4.2$\sigma$ in combination with previous measurement) are strengthening the need for new physics coupled to muons. In this letter, we propose a novel scenario in which Standard Model (SM) is augmented by an axion-like particle (ALP) and vector-like fermions. We find that such a model admits an excellent interpretation of recent muon $g-2$ measurement through quantum process featuring ALP interacting with muons and newly introduced fermions. Previously proposed explanations with ALPs utilize interactions with photons and/or SM fermions. Therefore, in this letter we complement and extend such scenarios. We also discuss collider prospects for the model as well as the possibility that ALP is long lived or stable dark matter (DM) candidate.