Abstract
We present high angular resolution (0.19 arcsec or ≈24 pc) Atacama Large Millimeter/submillimeter Array observations of the 12CO(3-2) line emission of the galaxy NGC 4751. The data provide evidence for the presence of a central supermassive black hole (SMBH). Assuming a constant mass-to-light ratio (M/L), we infer a SMBH mass MBH = 3.43+0.45−0.44 [stat, 3σ] +0.22−0.64 [sys] × 109 M⊙ and a F160W filter stellar M/L = 2.68 ± 0.11 [stat, 3σ] +0.10−0.80 [sys] M⊙/L⊙,F160W, where the first uncertainties are statistical and the second systematic. Assuming a linearly spatially varying M/L, we infer MBH = 2.79+0.75−0.57 [stat, 3σ] +0.75−0.45 [sys] × 109 M⊙. We also present SMBH mass estimates using the Jeans Anisotropic Modelling (JAM) method and Very Large Telescope SINFONI stellar kinematics. Assuming a cylindrically aligned velocity ellipsoid, we infer MBH = (2.52 ± 0.36) × 109 M⊙, while assuming a spherically aligned velocity ellipsoid we infer MBH = (3.24 ± 0.87) × 109 M⊙. The SMBH mass assuming a constant M/L is statistically consistent with that of the spherically aligned JAM model, whereas the mass assuming a linearly varying M/L is consistent with both JAM models within the uncertainties. Our derived masses are larger than, and inconsistent with, one previous stellar dynamical measurement using the Schwarzschild orbit-superposition method and the same SINFONI kinematics.
WISDOM Project - XXVI. Cross-checking supermassive black hole mass estimates from ALMA CO gas kinematics and SINFONI stellar kinematics in the galaxy NGC 4751
Monthly Notices of the Royal Astronomical Society, 542, 3, 2039-2059
Dominiak, Pandora; Cappellari, Michele; Bureau, Martin; Davis, Timothy A.; Sarzi, Marc; Ruffa, Ilaria; Iguchi, Satoru; Williams, Thomas G.; Zhang, Hengyue
(ADS) / (arXiv)