Researchers from the Italian Institute of Astrophysics have explained photon behavior during the brightest cosmic explosion recorded. Their findings could confirm the existence of dark matter particles and provide insights into their origins. The preprint of their study was published on arXiv.
In October 2022, scientists observed the most powerful cosmic explosion in history, named GRB 221009A, which occurred 2.4 billion light-years away and surpassed all previously registered events in brightness. This phenomenon, dubbed 'BOAT' (Brightest Of All Time), resulted from a star's death and the formation of a black hole.
Recently, astrophysicists detected anomalies in the data. Photons with energies exceeding 10 teraelectronvolts, recorded by the LHAASO observatory, should not have reached Earth due to interactions with cosmic radiation. A team led by Giorgio Galanti proposed an explanation based on the existence of axion-like particles. These hypothetical particles, predicted by string theory, could clarify photon behavior during interactions with magnetic fields and surrounding space.
Axion-like particles are among the leading candidates for dark matter, an invisible substance constituting up to 85% of the universe's mass, inferred from its gravitational effects on cosmic objects. Previously, traces of these particles were found in the light from distant blazars—active galaxies with powerful emissions. However, GRB 201009A presents a unique opportunity to study axions in the context of the brightest gamma-ray burst.
The researchers acknowledge that their hypothesis requires further validation. For instance, neutron stars may also be potent sources of axions, and studying them could help confirm the existence of these particles.