Coevolution of Supermassive Black Holes and Circumnuclear Disks

Understand

We propose a new evolutionary model of a supermassive black hole (SMBH) and a circumnuclear disk (CND), taking into account the mass-supply from a host galaxy and the physical states of CND.

• In the model, two distinct accretion modes depending on gravitational stability of the CND play a key role on accreting gas to a SMBH.
• (i) If the CMD is gravitationally unstable, energy feedback from supernovae (SNe) supports a geometrically thick, turbulent gas disk.
• The accretion in this mode is dominated by turbulent viscosity, and it is significantly larger than that in the mode (ii), i.e., the CMD is supported by gas pressure.