Oral Presentation

Magnetohydrodynamical Shocks powered by a rotating Black Hole

Author(s): Masaaki Takahashi (Aichi University of Education)

Presenter: Masaaki Takahashi (Aichi University of Education)

The standing magnetohydrodynamical (MHD) shocks by accreting plasma onto a rotating black hole is studied. Around a black hole with a magnetized accretion disk, a black hole
magnetosphere would be formed. In this magnetosphere, the magnetized plasma streams from the disk surface to the event horizon, and on the way to the horizon MHD shock can be generated so that the postshock plasma becomes so hot. Then,
this shocked hot plasma can be expected as a source of high-energy radiation, which is generated very close to the event horizon and carries to us a lot of information of the black hole spacetime. Specially, the formation of the hot plasma domain near the high latitude region of the horizon is very interesting as a source of primary X-ray emission for the broadened iron K emission line (see, e.g., Wilkins & Fabian 2012). We also discuss huge energy release powered by a rotating black hole at the MHD shock front, where the plasma's kinetic energy and the magnetic energy (Blandford-Znajek power 1977) can convert to radiative energy by considering negative energy postshock MHD flows (Takahashi & Takahashi 2010).