2024A&A...691A.114M

We analyzed Multi Unit Spectroscopic Explorer observations of 42 local z ≲ 0.1 type 1 active galactic nucleus (AGN) host galaxies taken from the Palomar-Green quasar sample and the close AGN reference survey. Our goal was to study the relation between the black hole mass (M_•) and bulge stellar velocity dispersion (σ_e) for type 1 active galaxies. The sample spans black hole masses of 10^6.0 - 10^9.2 M_⊙, bolometric luminosities of 10^42.9 - 10^46.0 erg s^–1, and Eddington ratios of 0.006 - 1.2. We avoided AGN emission by extracting the spectra over annular apertures. We modeled the calcium triplet stellar features and measured stellar velocity dispersions of σ_* = 60 - 230 km s^–1 for the host galaxies. We find stellar velocity dispersion values in agreement with previous measurements for local (z ≲ 0.1) AGN host galaxies, but slightly lower compared with those reported for nearby X-ray-selected type 2 quasars. Using a novel annular aperture correction recipe to estimate σ_e from σ_* that considers the bulge morphology and observation beam-smearing, we estimate flux-weighted σ_e = 60 - 250 km s^–1. If we consider the bulge type when estimating M_•, we find no statistical difference between the distributions of AGN hosts and the inactive galaxies on the M_•-σ_e plane for M_• ≲ 10⁸ M_⊙. Conversely, if we do not consider the bulge type when computing M_•, we find that both distributions disagree. We find no correlation between the degree of offset from the M_•-σ_e relation and Eddington ratio for M_• ≲ 10⁸ M_⊙. The current statistics preclude firm conclusions from being drawn for the high-mass range. We argue these observations support notions that a significant fraction of the local type 1 AGNs and quasars have undermassive black holes compared with their host galaxy bulge properties.