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The origin of the tight scaling relation between the mass of supermassive black holes (SMBHs; MBH) and their host-galaxy properties remains unclear. Active galactic nuclei (AGNs) probe phases of ongoing SMBH growth and offer the only opportunity to measure MBH beyond the local Universe. However, determining an AGN's host galaxy's stellar velocity dispersion, σå, and its galaxy dynamical mass, Mdyn, is complicated by AGN contamination, aperture effects, and different host-galaxy morphologies. We select a sample of AGNs for which MBH has been independently determined to high accuracy by state-of-the-art techniques: dynamical modeling of the reverberation signal and spatially resolving the broad-line region with the Very Large Telescope Interferometer/GRAVITY. Using integral-field spectroscopic observations, we spatially map the host-galaxy stellar kinematics across the galaxy and bulge effective radii. We find that the dynamically hot component of galaxy disks correlates with MBH; however, the correlations are tightest for aperture-integrated σå measured across the bulge. Accounting for the different MBH distributions, we demonstrate—for the first time—that AGNs follow the same MBH–σ and MBH–M_bulge,dyn relations as quiescent galaxies. We confirm that the classical approach of determining the virial factor as a sample average, yielding log f = 0.65 +/- 0.18, is consistent with the average f from individual measurements. The similarity between the underlying scaling relations of AGNs and quiescent galaxies implies that the current AGN phase is too short to have altered black hole masses on a population level. These results strengthen the local calibration of f for measuring single-epoch MBH in the distant Universe. 

ABSTRACT Galaxy mergers are crucial to understanding galaxy evolution, therefore we must determine their observational signatures to select them from large IFU galaxy samples such as MUSE and SAMI. We employ 24 high-resolution idealized hydrodynamical galaxy merger simulations based on the ‘Feedback In Realistic Environment’ (FIRE-2) model to determine the observability of mergers to various configurations and stages using synthetic images and velocity maps. Our mergers cover a range of orbital configurations at fixed 1:2.5 stellar mass ratio for two gas rich spirals at low redshift. Morphological and kinematic asymmetries are computed for synthetic images and velocity maps spanning each interaction. We divide the interaction sequence into three: (1) the pair phase; (2) the merging phase; and (3) the post-coalescence phase. We correctly identify mergers between first pericentre passage and 500 Myr after coalescence using kinematic asymmetry with 66 per cent completeness, depending upon merger phase and the field of view of the observation. We detect fewer mergers in the pair phase (40 per cent) and many more in the merging and post-coalescence phases (97 per cent). We find that merger detectability decreases with field of view, except in retrograde mergers, where centrally concentrated asymmetric kinematic features enhances their detectability. Using a cut-off derived from a combination of photometric and kinematic asymmetry, we increase these detections to 89 per cent overall, 79 per cent in pairs, and close to 100 per cent in the merging and post-coalescent phases. By using this combined asymmetry cut-off we mitigate some of the effects caused by smaller fields of view subtended by massively multiplexed integral field spectroscopy programmes.