WISDOM Project–XXVI. Cross-checking supermassive black hole mass estimates from ALMA CO gas kinematics and SINFONI stellar kinematics in the galaxy NGC 4751

Journal article

We present high angular resolution (0.19 arcsec or pc) Atacama Large Millimeter/submillimeter Array observations of the CO(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 (), we infer a SMBH mass M and a F160W filter stellar M/L, where the first uncertainties are statistical and the second systematic. Assuming a linearly spatially varying , we infer M and , where R is the galactocentric radius. We also present SMBH mass estimates using the Jeans Anisotropic Modelling (JAM) method and Very Large Telescope Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) stellar kinematics. Assuming a cylindrically aligned velocity ellipsoid (JAM), we infer M, and while assuming a spherically aligned velocity ellipsoid (JAM), we infer M. The SMBH mass assuming a constant is statistically consistent with that of JAM, whereas the mass assuming a linearly varying is consistent with both JAM and JAM (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.

Authors: Dominiak, P; Cappellari, M; Bureau, M; Davis, TA; Sarzi, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Oxford University Press
• Journal: Monthly Notices of the Royal Astronomical Society
• Volume: 542
• Issue: 3
• Pages: 2039-2059
• Publication date: 2025-08-13
• Acceptance date: 2025-08-11
• DOI: 10.1093/mnras/staf1338
• EISSN: 1365-2966
• ISSN: 0035-8711
• Language: English
• Keywords: galaxies: ISM; galaxies: nuclei; galaxies: kinematics and dynamics; galaxies: individual: NGC 4751; galaxies: elliptical and lenticular, cD