2016ApJ...822L..28B

We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 3 observations of CO(2-1) emission from the circumnuclear disk in the E/S0 galaxy NGC 1332 at 0.''044 resolution. The disk exhibits regular rotational kinematics and central high-velocity emission (±500 km/s) consistent with the presence of a compact central mass. We construct models for a thin, dynamically cold disk in the gravitational potential of the host galaxy and black hole and fit the beam-smeared model line profiles directly to the ALMA data cube. Model fits successfully reproduce the disk kinematics out to r=200 pc. Fitting models just to spatial pixels within projected r=50 pc of the nucleus (two times larger than the black hole's gravitational radius of influence), we find {M}_BH=({6.64}{-0.63}^{+0.65})×{10}^{8} {M}_☉ . This observation demonstrates ALMA's powerful capability to determine the masses of supermassive black holes by resolving gas kinematics on small angular scales in galaxy nuclei.