Open particle accelerators destroying the stars

Scientists have identified the mechanism of formation of high-energy radiation.

Russian scientists together with colleagues from Hong Kong and Taiwan explained the origin of high-energy cosmic rays, the source of which was not known before. The researchers found that they can occur in the Fermi bubbles, formed due to a supermassive black hole destroying a star. Briefly about the scientific work described in the press release.

Cosmic rays — elementary particles and atomic nuclei moving with high energies. Their sources are usually in a supernova, in which the formation of shock waves. The recent acceleration of particles to energies of 1015 electron volts (eV). However, there are rays where the value of this parameter much more.

Scientists have identified a possible mechanism of formation of such high-energy radiation. It involves the Fermi bubbles, extending 50 thousand light-years above and below the plane of the disk of the galaxy. The simulation results showed that these areas formed as a result of the emission of energy and matter, provoked by the tidal destruction of stars near the giant black hole at the center of the milky Way. The Fermi bubbles are themselves a source of radiation.

Researchers have shown that x-rays and gamma-rays inside the bubbles indicate processes involving electrons accelerated by shock waves to velocities close to light. However, in this case needs to accelerate not only electrons, but the particles and the atomic nucleus. However, the latter do not lose energy in the galactic halo can scatter around the milky way.

This model explains the observed spectrum of cosmic rays. The Fermi bubbles may re-disperse the particles, accelerated by a supernova, bringing them to energy that exceeds a threshold to 1015 eV.

paradox