A global analysis of axion-like particle interactions using SMEFT fits

TL;DR

This paper performs a comprehensive global analysis of axion-like particle interactions within the SMEFT framework, deriving indirect bounds on ALP couplings from existing experimental data, which are competitive with direct searches.

Contribution

It introduces a novel global analysis method combining Higgs, top, and low-energy data to constrain ALP couplings in a model-independent way.

Findings

Derived bounds on ALP couplings are stronger than direct bounds in the GeV-TeV mass range.

The analysis demonstrates the importance of SMEFT contributions in constraining ALP interactions.

Results are applicable to a wide class of ALP models, providing new insights into their parameter space.

Abstract

In the presence of an axion or axion-like particle (ALP) that couples to the Standard Model via dimension-five interactions, dimension-six SMEFT interactions are generated via renormalization-group evolution. As many of these SMEFT contributions are experimentally tightly constrained, this "ALP-SMEFT interference" can be used to derive indirect bounds on the ALP couplings to the Standard Model particles. We present a global analysis of the Wilson coefficients of the ALP effective Lagrangian based on Higgs, top, and low-energy data. The obtained bounds are model independent and are competitive or even stronger than direct bounds in the GeV to TeV ALP-mass range.