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Broad-line variability in NGC 5548

Journal Article · · Astrophys. J.; (United States)
DOI:https://doi.org/10.1086/166310· OSTI ID:6990567
The possible explanations for the variability behavior of the He II 4686A and H-beta lines in the Seyfert galaxy NGC 5548 as observed by Peterson and Ferland (1986) are discussed. The range of variability expected from these lines is explored according to the standard models for broad-line clouds, assuming changes in the values of various of the clouds defining parameters. When compared with model predictions, the observed line variability suggests the existence of a strong, variable EUV component of the ionizing spectrum and of two populations of clouds which differ in their velocity distributions and in their response to continuum variations. 19 references.
Research Organization:
NASA, Goddard Space Flight Center, Greenbelt, MD (USA)
OSTI ID:
6990567
Journal Information:
Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 328; ISSN ASJOA
Country of Publication:
United States
Language:
English

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