2011/03/10 by Hermine Landt, Misty C. Bentz, Bradley M. Peterson +4 · 24 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Black hole (networking) #Extinction (optical mineralogy) #Galaxies: Formation, Evolution, Phenomena #Photoionization #Starlight #Supermassive black hole #Ultraviolet #Wavelength #astro-ph.CO
paper · pdf · doi:10.1111/j.1745-3933.2011.01047.x
published in Monthly Notices of the Royal Astronomical Society Letters 413(1), L106-L109 (Oxford University Press) · 5 pages, 2 figures, accepted by MNRAS Letters
arxiv created 2011/03/10 · openalex publication_date 2011/03/31 · arxiv updated 2015/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Abstract Black hole masses for samples of active galactic nuclei (AGNs) are currently estimated from single-epoch optical spectra. In particular, the size of the broad-line emitting region needed to compute the black hole mass is derived from the optical or ultraviolet continuum luminosity. Here we consider the relationship between the broad-line region size, R, and the near-infrared (near-IR) AGN continuum luminosity, L, as the near-IR continuum suffers less dust extinction than at shorter wavelengths and the prospects for separating the AGN continuum from host-galaxy starlight are better in the near-IR than in the optical. For a relationship of the form R∝Lα, we obtain for a sample of 14 reverberation-mapped AGN a best-fitting slope of α= 0.5 ± 0.1, which is consistent with the slope of the relationship in the optical band and with the value of 0.5 naïvely expected from photoionization theory. Black hole masses can then be estimated from the near-IR virial product, which is calculated using the strong and unblended Paschen broad emission lines (Paα or Paβ).