Constraints on axion-like particles with the Perseus Galaxy Cluster with MAGIC

TL;DR

This study used MAGIC telescope data to search for axion-like particles in the Perseus Galaxy Cluster, setting new limits on their properties by analyzing gamma-ray spectra without detecting any ALP signals.

Contribution

It presents the most stringent constraints to date on ALP parameters around 50 neV, using a full likelihood approach and detailed magnetic field modeling.

Findings

No statistical evidence of ALPs was found.

Excluded ALP models in the sub-micro eV mass range.

Set new upper limits on ALP-photon coupling constants.

Abstract

Axion-like particles (ALPs) are pseudo-Nambu-Goldstone bosons that emerge in various theories beyond the standard model. These particles can interact with high-energy photons in external magnetic fields, influencing the observed gamma-ray spectrum. This study analyzes 41.3 hrs of observational data from the Perseus Galaxy Cluster collected with the MAGIC telescopes. We focused on the spectra the radio galaxy in the center of the cluster: NGC 1275. By modeling the magnetic field surrounding this target, we searched for spectral indications of ALP presence. Despite finding no statistical evidence of ALP signatures, we were able to exclude ALP models in the sub-micro electronvolt range. Our analysis improved upon previous work by calculating the full likelihood and statistical coverage for all considered models across the parameter space. Consequently, we achieved the most stringent limits to date for ALP masses around 50 neV, with cross sections down to $g_{a\gamma} = 3 \times 10^{-12}$ GeV$^{-1}$.