2004/02/29 by Karen M. Leighly · 4 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Doubly ionized oxygen #Emission spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #Ionization #Outflow #Photoionization #Physics #Spectral line #astro-ph
paper · pdf · doi:10.1086/422089
published as Astrophys.J. 611 (2004) 125-152 · 45 pages, 15 figures (4 color), accepted for publication in ApJ, abstract shortened
arxiv created 2004/04/11 · openalex publication_date 2004/08/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present modeling to explore the conditions of the broad-line-emitting gas in two extreme narrow-line Seyfert 1 galaxies, using the observational results described in the first paper of this series. Photoionization modeling using CLOUDY was conducted for the broad blueshifted wind lines and the narrow, symmetric, rest-wavelength-centered disk lines separately. A broad range of physical conditions was explored for the wind component, and a figure of merit was used to quantitatively evaluate the simulation results. Of the three minima in the figure-of-merit parameter space, we favor the solution characterized by an X-ray-weak continuum, elevated abundances, a small column density (log N H ≈ 21.4), a relatively high ionization parameter (log U ≈ -1.2 to -0.2), a wide range of densities (log n ≈ 7-11), and a covering fraction of ~0.15. The presence of low-ionization emission lines implies that the disk component is optically thick to the continuum, and the Si III]/C III] ratio implies a density of 10 10 -10 10.25 cm -3 . A low ionization parameter (log U = -3) is inferred for the intermediate-ionization lines, unless the continuum is "filtered" through the wind before illuminating the intermediate-line-emitting gas, in which case log U = -2.1. The location of the emission regions was inferred from the photoionization modeling and a simple "toy" dynamical model. A large black hole mass (1.3 × 10 8 M ☉ ) radiating at 11% of the Eddington luminosity is consistent with the kinematics of both the disk and wind lines, and an emission radius of ~10 4 R S is inferred for both. We compare these results with previous work and discuss implications.