Two likely explanations
There are two likely explanations behind the formation of the mini-halo.
One is that there are supermassive black holes which lie at the hearts of galaxies within a cluster and can eject streams of high-energy particles into space.
However, astronomers are still trying to understand how these particles would be able to migrate away from the black hole to create such a gigantic cloud of particles, while maintaining so much of their energy.
The second explanation is cosmic particle collisions.
This is when charged particles within the hot plasma of the galaxy cluster collide at near-light speeds, smashing apart into the highly energetic particles that make up the mini-halo.
The astronomers say their finding offers a rare look at what galaxy clusters were like just after they formed. It not only shows that galaxy clusters have been infused with high-energy particles for billions of years more than previously known but also allows scientists to study where these high-energy particles come from.
"It’s astonishing to find such a strong radio signal at this distance," said Roland Timmerman, a Durham University (U.K.) astronomer who co-led the discovery with Hlavacek-Larrondo. "It means these energetic particles and the processes creating them have been shaping galaxy clusters for nearly the entire history of the universe.”
