We present a survey of 72 Seyfert galaxies and quasars observed by the it Far Ultraviolet Spectroscopic Explorer (FUSE). We have determined that 72 of 253 available active galactic nuclei (AGN) targets are viable targets for detection of intrinsic absorption lines. We examined these spectra for signs of intrinsic absorption in the O VI doublet (lambda 1031.9, 1037.6) and Lyman beta (lambda 1025.7). The fraction of Seyfert 1 galaxies and low-redshift quasars at z < 0.15 that show evidence of intrinsic UV absorption is ~50%, which is slightly lower than Crenshaw et al. (1999) found (60%) based on a smaller sample of Seyfert 1 galaxies observed with the Hubble Space Telescope (HST). With this new fraction we find a global covering factor of the absorbing gas with respect to the central nucleus of ~0.4. Our survey is to date the largest searching for intrinsic UV absorption with high spectral resolution, and is the first step toward a more comprehensive study of intrinsic absorption in low-redshift AGN.

生成讲解博客的中文版本

生成AI智能校验的中文版本