The Supermassive Black Hole of M87 and the Kinematics of Its Associated Gaseous Disk

摘要

We have obtained long-slit observations of the circumnuclear region of M87 at three different loca- tions, with a spatial sampling of 0".28 using the Faint Object Camera f/48 spectrograph on board HST. These data allow us to determine the rotation curve of the inner ～1" of the ionized gas disk in [O Ⅱ] λ3727 to a distance as close as 0".07 (≈5 pc) to the dynamic center, thereby significantly improving on both the spatial resolution and coverage of previous FOS observations. We have modeled the kinematics of the gas under the assumption of the existence of both a central black hole and an extended central mass distribution, taking into account the effects of the instrumental PSF, the intrinsic luminosity dis- tribution of the line, and the finite size of the slit.