Axion-like ALPs

TL;DR

This paper develops more constrained effective field theories for axion-like particles by enforcing true axion-like properties, making them better benchmarks for experimental searches.

Contribution

It introduces a method to impose true axion-like symmetry conditions on generic ALP EFTs, inspired by DFSZ and KSVZ models.

Findings

Defined constrained ALP EFTs with true axion-like properties

Provided benchmark scenarios for collider and low-energy experiments

Enhanced the theoretical consistency of ALP phenomenology

Abstract

The Effective Field Theory (EFT) Lagrangian for a generic axion-like particle (ALP) has many free parameters, and leaves quite some freedom for the expected phenomenology. In this work, we set up more constrained EFTs by enforcing true axion-like properties for the ALP. Indeed, though the Peccei-Quinn symmetry of the QCD axion is anomalous, it is so in specific ways, and this shows up as consistency conditions between the gauge boson and fermion couplings. We propose to enforce such conditions, as inspired from the DFSZ and KSVZ scenarios, on the generic ALP EFTs. These truly axion-like ALP EFTs are then particularly well-suited as benchmark scenarios, to be used in the search for ALPs both at colliders and at low-energy experiments.