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

Journal Article · Tue Jul 01 04:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/789/1/17· OSTI ID:22356514

Ho, Luis C. ^[1]; Kim, Minjin ^[2]

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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)

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 hosts 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.

• OSTI ID: 22356514
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 789; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BLACK HOLES
CALIBRATION
CLASSIFICATION
COMPARATIVE EVALUATIONS
DECOMPOSITION
DISPERSIONS
EMISSION
GALAXIES
GALAXY NUCLEI
GAS UTILITIES
IMAGES
MASS
QUASARS
SPACE
VELOCITY