How can active galaxies with supermassive black holes accelerate cosmic rays?

Active galaxies, which contain a supermassive black hole at their center, accelerate particles through the process of accretion. As matter spirals toward the black hole, it forms an accretion disk where gravitational energy is converted into heat and high-speed particle motion.12

This central engine supplies the energy required to power radio jets—twin beams of relativistic particles that are ejected from the nucleus at speeds approaching that of light. These jets transport energy from the galaxy's core to distant radio lobes, where they impact the surrounding medium at "hot spots" of enhanced emission. While the exact details of particle acceleration processes remain a subject of ongoing study, it is understood that these relativistic beams and the associated magnetic fields play a critical role in generating high-energy radiation and accelerating particles to extreme velocities.3