Asymmetric drift in MaNGA: Mass and radially-dependent stratification rates in galaxy disks
Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2024) stae1207
WISDOM Project -- XIX. Figures of merit for supermassive black hole mass measurements using molecular gas and/or megamaser kinematics
(2024)
MaNGA DynPop – V. The dark-matter fraction versus stellar velocity dispersion relation and stellar initial mass function variations in galaxies: dynamical models and full spectrum fitting of integral-field spectroscopy
Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2024) stae1116
WISDOM Project – XIX. Figures of merit for supermassive black hole mass measurements using molecular gas and/or megamaser kinematics
Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2024) stae1106
Abstract:
<jats:title>Abstract</jats:title> <jats:p>The mass (MBH) of a supermassive black hole (SMBH) can be measured using spatially-resolved kinematics of the region where the SMBH dominates gravitationally. The most reliable measurements are those that resolve the smallest physical scales around the SMBHs. We consider here three metrics to compare the physical scales probed by kinematic tracers dominated by rotation: the radius of the innermost detected kinematic tracer Rmin normalised by respectively the SMBH’s Schwarzschild radius (RSchw ≡ 2GMBH/c2, where G is the gravitational constant and c the speed of light), sphere-of-influence (SOI) radius ($R_\mathrm{SOI}\equiv GM_\mathrm{BH}/\sigma _\mathrm{e}^2$, where σe is the stellar velocity dispersion within the galaxy’s effective radius) and equality radius (the radius Req at which the SMBH mass equals the enclosed stellar mass, MBH = M*(Req), where M*(R) is the stellar mass enclosed within the radius R). All metrics lead to analogous simple relations between Rmin and the highest circular velocity probed Vc. Adopting these metrics to compare the SMBH mass measurements using molecular gas kinematics to those using megamaser kinematics, we demonstrate that the best molecular gas measurements resolve material that is physically closer to the SMBHs in terms of RSchw but is slightly farther in terms of RSOI and Req. However, molecular gas observations of nearby galaxies using the most extended configurations of the Atacama Large Millimeter/sub-millimeter Array can resolve the SOI comparably well and thus enable SMBH mass measurements as precise as the best megamaser measurements.</jats:p>WISDOM Project -- XXIV. Cross-checking supermassive black hole mass estimates from ALMA CO gas kinematics and SINFONI stellar kinematics in the galaxy NGC 4751
(2024)