Axion-like Particle Searches at DarkQuest

TL;DR

This paper evaluates DarkQuest's potential to detect axion-like particles (ALPs) in the MeV to GeV range, focusing on their production and decay via photon or gluon interactions, and addresses previous calculation inconsistencies.

Contribution

It provides a detailed analysis of DarkQuest's sensitivity to ALPs, especially correcting production and decay calculations for gluon-coupled ALPs, and explores new parameter space coverage.

Findings

DarkQuest can probe previously inaccessible ALP parameter regions.

Corrected calculations improve the reliability of ALP detection predictions.

The study constrains existing ALP parameter space with new insights.

Abstract

Axion-like particles (ALPs) interacting with the Standard Model can be abundantly produced in proton beam fixed-target experiments. Looking for their displaced decays is therefore an effective search strategy for ALPs with a mass in the MeV to GeV range. Focusing on the benchmark models where the ALP interacts dominantly with photons or gluons, we show that the proposed DarkQuest experiment at Fermilab will be able to test parameter space which has been previously inaccessible. We pay particular attention to the self-consistency of gluon-coupled ALP production and decay calculations, which has been recently shown to be a problem in many existing predictions. We also apply these results to explore existing constraints in the ALP parameter space.