Journal
ASTROPHYSICAL JOURNAL
Volume 590, Issue 1, Pages 174-180Publisher
UNIV CHICAGO PRESS
DOI: 10.1086/374920
Keywords
galaxies : active; galaxies : individual (NGC 5548); galaxies : nuclei; galaxies : Seyfert
Categories
Ask authors/readers for more resources
We compare X-ray and UV spectroscopic observations of NGC 5548. Both data sets show O VI absorption troughs associated with the active galactic nuclei outflow from this galaxy. We find that the robust lower limit on the column density of the O VI X-ray trough is 7 times larger than the column density found in a study of the O VI UV troughs. This discrepancy suggests that column densities inferred for UV troughs of Seyfert galaxy outflows are often severely underestimated. We identify the physical limitations of the UV Gaussian modeling as the probable explanation of the O VI column density discrepancy. Specifically, Gaussian modeling cannot account for a velocity-dependent covering fraction, and it is a poor representation for absorption associated with a dynamical outflow. Analysis techniques that use a single covering fraction value for each absorption component suffer from similar limitations. We conclude by suggesting ways to improve the UV analysis.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available