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Title: The black hole mass scale of classical and pseudo bulges in active galaxies

The mass estimator used to calculate black hole (BH) masses in broad-line active galactic nuclei (AGNs) relies on a virial coefficient (the 'f factor') that is determined by comparing reverberation-mapped (RM) AGNs with measured bulge stellar velocity dispersions against the M {sub BH}-σ{sub *} relation of inactive galaxies. It has recently been recognized that only classical bulges and ellipticals obey a tight M {sub BH}-σ{sub *} relation; pseudobulges have a different zero point and much larger scatter. Motivated by these developments, we reevaluate the f factor for RM AGNs with available σ{sub *} measurements, updated Hβ RM lags, and new bulge classifications based on detailed decomposition of high-resolution ground-based and space-based images. Separate calibrations are provided for the two bulge types, whose virial coefficients differ by a factor of ∼2: f = 6.3 ± 1.5 for classical bulges and ellipticals and f = 3.2 ± 0.7 for pseudobulges. The structure and kinematics of the broad-line region, at least as crudely encoded in the f factor, seems to be related to the large-scale properties or formation history of the bulge. Lastly, we investigate the bulge stellar masses of the RM AGNs, show evidence for recent star formation in the AGN hostsmore » that correlates with Eddington ratio, and discuss the potential utility of the M {sub BH}-M {sub bulge} relation as a more promising alternative to the conventionally used M {sub BH}-σ{sub *} relation for future refinement of the virial mass estimator for AGNs.« less
Authors:
 [1] ;  [2]
  1. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)
  2. The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
Publication Date:
OSTI Identifier:
22356514
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 789; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; CALIBRATION; CLASSIFICATION; COMPARATIVE EVALUATIONS; DECOMPOSITION; DISPERSIONS; EMISSION; GALAXIES; GALAXY NUCLEI; GAS UTILITIES; IMAGES; MASS; QUASARS; SPACE; VELOCITY