• Two teams independently searched for axions, a dark matter candidate, by analyzing X-ray emissions from starburst galaxies (M82 and M87) using NuSTAR telescope data.
• One team searched for lightweight axions converting into X-ray photons via magnetic fields, while the other looked for heavy axions decaying into observable photons.
• Both teams found no axion signals but established new constraints on axion properties, contributing to the broader understanding of dark matter.

Two independent research teams have focused on starburst galaxies as potential axion factories, seeking to detect these hypothetical particles, which are considered leading candidates for dark matter. They analyzed X-ray data from the Nuclear Spectroscopic Telescope Array (NuSTAR) to detect specific signatures related to axion production and decay. The teams investigated galaxies M82 and M87, looking for spectral distortions indicative of axions. While neither team detected a definitive axion signal, their research provided valuable constraints on the potential properties of axions within specific mass ranges.

• What: Two research teams independently searched for axions by analyzing X-ray data from starburst galaxies M82 and M87.
• Who: One team consisted of Orion Ning and Benjamin R. Safdi. The other team included Francisco R. Candón, Damiano F. G. Fiorillo, Giuseppe Lucente, Edoardo Vitagliano, and Julia K. Vogel.
• When: The research was published on May 1, 2025. The NuSTAR telescope, used for data collection, was launched in 2012.
• Where: The research focused on the starburst galaxies M82 and M87.

The search for axions is motivated by the potential to solve problems with the strong force and to explain dark matter. This research, employing observations of entire galaxies, offers a novel approach to axion detection, complementing laboratory experiments and observations of individual stars. The fact that no signal was detected allows for refining the range of potential axion masses and properties. The analysis also highlights the complex astrophysical environments of galaxies, making accurate modeling of axion production challenging but crucial.

Axions are some of the best motivated candidates at the moment for physics beyond the standard model.

We think of stars as axion factories. The Sun is the closest and thus the simplest factory to deal with, but there are maybe better sources out there.

We’ve taken this factory analogy to the extreme.

If these particles exist, they would outshine what you already observe in x rays.

We are gaining new insights into axions by looking for them in data collected by astronomers who are interested in these galaxies for entirely different reasons.

Two independent teams have probed starburst galaxies for axion signatures using X-ray data from the NuSTAR telescope. While neither team detected a signal, their research has contributed valuable constraints on the properties of axions, narrowing down the search parameters for future experiments. Future research will explore a broader set of axion production mechanisms and target other galaxies, continuing the quest to understand dark matter.