Shock acceleration in active galactic nuclei and quasars

A model of spherical accretion on a massive black hole as the energy source for active galactic nuclei and quasars is considered. According to the model, the kinetic energy of the infalling material is randomized by a collisionless shock around the black hole. Relativistic protons are produced with high efficiency via first order Fermi shock acceleration and, because their kinetic energy is much larger than the gravitational potential energy, do not fall into the black hole. The model can produce relativistic particles with flat spectra needed to account for the radiation from these sources, including their broad band spectral characteristics. Since all electrons are secondaries resulting from proton-proton collisions throughout the volume of the source, this model avoids the Compton catastrophe problem.