Formation and collimation of relativistic jets - Application to the classification of FR I and FR II radio galaxies

We investigate the classification of Active Galactic nuclei (AGN) of powerful jets FR I and FR II. We use a steady axisymmetric self-similar model of relativistic magnetohydrodynamics (GRMHD) outflows originating at the hot coronal magnetosphere of a Schwarzschild black hole and surrounding accretion disk. We demonstrate that the differences between the jets of FR II and FR I are related to the rotation of corona. When the rotation slows down and deviates strongly form the Keplerian rotation, the Poyting flux injected in the jet decreases. As result, the efficiency of the magnetic pinching decreases and influence of the external medium in the jet increases, so the proprieties of jets change from that of FR II to FR I.