Energy, momentum and mass outflows and feedback from thick accretion discs around rotating black holes

Abstract

Using long-duration general relativistic magnetohydrodynamic simulations of\nradiatively inefficient accretion discs, the energy, momentum and mass outflow\nrates from such systems are estimated. Outflows occur via two fairly distinct\nmodes: a relativistic jet and a sub-relativistic wind. The jet power depends\nstrongly on the black hole spin and on the magnetic flux at the horizon. Unless\nthese are very small, the energy output in the jet dominates over that in the\nwind. For a rapidly spinning black hole accreting in the magnetically arrested\nlimit, it is confirmed that jet power exceeds the total rate of accretion of\nrest mass energy. However, because of strong collimation, the jet probably does\nnot have a significant feedback effect on its immediate surroundings. The power\nin the wind is more modest and shows a weaker dependence on black hole spin and\nmagnetic flux. Nevertheless, because the wind subtends a large solid angle, it\nis expected to provide efficient feedback on a wide range of scales inside the\nhost galaxy. Empirical formulae are obtained for the energy and momentum\noutflow rates in the jet and the wind.\n