Abstract
The spatial and radial velocity distribution of broad-line-emitting gas in the Seyfert 1 galaxy NGC 5548 is examined through the process of reverberation mapping, which is done by detailed comparison of continuum and emission-line variations. Recent spectroscopic monitoring of NGC 5548 with HST and IUE allows us to resolve the "transfer function" (TF) that relates the continuum and emission-line variability. We also examine the radial velocity-resolved TFs, and confirm that predominantly radial motions of the line-emitting clouds can be excluded. We find that a broad-line region comprised of clouds that are orbiting a central source of mass ~108 M☉ along randomly inclined Keplerian orbits and irradiated by a beamed continuum source yields a TF and line profile that are qualitatively consistent with the observations. In this model, the clouds that produce the variable C IV emission lie within 12 lt-days of the central source, and the continuum radiation is confined to a wide biconical beam (semi-opening angle 35°-60°) with the observer viewing into the cone.
Document Type
Article
Publication Date
11-10-1995
Digital Object Identifier (DOI)
http://dx.doi.org/10.1086/309750
Repository Citation
Wanders, Ignaz; Goad, Mike R.; Korista, Kirk T.; Peterson, Bradley M.; Horne, Keith; Ferland, Gary J.; Koratkar, Anuradha P.; Pogge, Richard W.; and Sheilds, Joseph C., "The Geometry and Kinematics of the Broad-Line Region in NGC 5548 from HST and IUE Observations" (1995). Physics and Astronomy Faculty Publications. 162.
https://uknowledge.uky.edu/physastron_facpub/162
Notes/Citation Information
Published in The Astrophysical Journal Letters, v. 453, no. 2, p. L87-L90.
© 1995. The American Astronomical Society. All rights reserved.
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