A Far-Ultraviolet Spectroscopic Survey of Low-Redshift AGN

Using the Far Ultraviolet Spectroscopic Explorer (FUSE) we have obtained 87 spectra of 57 low-redshift (z < 0.15) active galactic nuclei (AGN). This sample comprises 53 Type 1 AGN and 4 Type 2. All the Type 1 objects show broad O vi λ1034 emission; two of the Type 2s show narrow O vi emission. In addition to O vi, we also identify emission lines due to C iii λ977, C iii λ991, S iv λλ1062, 1072, and He ii λ1085 in many of the Type-1 AGN. Of the Type 1 objects, 30 show intrinsic absorption by the O vi λλ1032, 1038 doublet. Most of these intrinsic absorption systems show multiple components with intrinsic widths of 100 km s spread over a blue-shifted velocity range of less than 1000 kms. Galaxies in our sample with existing X-ray or longer wavelength UV observations also show C iv absorption and evidence of a soft X-ray warm absorber. In some cases, a UV absorption component has physical properties similar to the X-ray absorbing gas, but in others there is no clear physical correspondence between the UV and X-ray absorbing components. Models in which a thermally driven wind evaporates material from the obscuring torus naturally produce such inhomogeneous flows.