2003/06/09 by D. W. Xu, Da Xu, S. Komossa +7 · 32 citations
Chemistry · Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Blueshift #Chemistry #Emission spectrum #Flux (metallurgy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Line (geometry) #Optics #Physics #ROSAT #Redshift #Spectral line #X-ray Spectroscopy and Fluorescence Analysis #astro-ph
paper · pdf · doi:10.1086/374978
published in The Astrophysical Journal 590(1), 73-85 (IOP Publishing) · ApJ in press, 7 figures included
arxiv created 2003/06/09 · openalex publication_date 2003/06/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
This work studies the optical emission line properties of a sample of 155 low-redshift bright X-ray-selected ROSAT Seyfert 1-type active galactic nuclei for which adequate signal-to-noise ratio spectroscopic observations are available. We measured emission-line properties by performing multicomponent fits to the emission-line profiles, covering the effect of blended iron emission. We also obtained continuum parameters, including 250 eV X-ray luminosities derived from the ROSAT database. In addition, the measured properties are gathered for a correlation analysis, which confirms the well-known relations between the strengths of Fe II, [O III] emission and the X-ray slope. We also detect striking correlations between Hβ redshift (or blueshift) and flux ratios of Fe II to Hβ broad component and [O III] to Hβ narrow component. These trends are most likely driven by the Eddington ratio.