Accretion of Supermassive Black Holes in Elliptical Galaxies

We present high-resolution, three-dimensional hydrodynamic simulations of the fueling of the supermassive black holes(SMBHs) in elliptical galaxies from galactic scale, taking M87* as a typical case. The simulations include radiative cooling and heating, and span nearly 5 orders of magnitude in radius, reaching all the way down to parsec scale. We investigate the cooling and heating properties of the accretion flow and the multiphase structure of the gas outside and inside the Bondi radius. The simulations illustrate the connection between the black hole accretion rate at small radii and the physical conditions at large radii. Using the results, we also provide more realistic initial conditions for simulations of the black hole accretion disk at the event horizon scale, which help to interpret Event Horizon Telescope observations of M87.