2010ApJ...721...26G -
Astrophys. J., 721, 26-45 (2010/September-3)
Precise black hole masses from megamaser disks: black hole-bulge relations at low mass.
GREENE J.E., PENG C.Y., KIM M., KUO C.-Y., BRAATZ J.A., IMPELLIZZERI C.M.V., CONDON J.J., LO K.Y., HENKEL C. and REID M.J.
Abstract (from CDS):
The black hole (BH)-bulge correlations have greatly influenced the last decade of efforts to understand galaxy evolution. Current knowledge of these correlations is limited predominantly to high BH masses (MBH≳108 M☉) that can be measured using direct stellar, gas, and maser kinematics. These objects, however, do not represent the demographics of more typical L < L* galaxies. This study transcends prior limitations to probe BHs that are an order of magnitude lower in mass, using BH mass measurements derived from the dynamics of H2 O megamasers in circumnuclear disks. The masers trace the Keplerian rotation of circumnuclear molecular disks starting at radii of a few tenths of a pc from the central BH. Modeling of the rotation curves, presented by Kuo et al., yields BH masses with exquisite precision. We present stellar velocity dispersion measurements for a sample of nine megamaser disk galaxies based on long-slit observations using the B&C spectrograph on the Dupont telescope and the Dual Imaging Spectrograph on the 3.5 m telescope at Apache Point. We also perform bulge-to-disk decomposition of a subset of five of these galaxies with Sloan Digital Sky Survey imaging. The maser galaxies as a group fall below the MBH-σ* relation defined by elliptical galaxies. We show, now with very precise BH mass measurements, that the low-scatter power-law relation between MBH and σ*seen in elliptical galaxies is not universal. The elliptical galaxy MBH-σ* relation cannot be used to derive the BH mass function at low mass or the zero point for active BH masses. The processes (perhaps BH self-regulation or minor merging) that operate at higher mass have not effectively established an MBH-σ* relation in this low-mass regime.
Abstract Copyright:
∼
Journal keyword(s):
galaxies: active - galaxies: bulges - galaxies: nuclei - galaxies: Seyfert
CDS comments:
Calibrator CD 32 is not identified.
Simbad objects:
40
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2010ApJ...721...26G and select 'bookmark this link' or equivalent in the popup menu