Relation between the ionizing continuum and the emission lines in Fairall 9

Bibcode
1989ApJ...343..135B
DOI
10.1086/167691
Binette, Luc; Prieto, Almudena; Szuszkiewicz, Ewa; Zheng, Wei
Bibliographical reference

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 343, Aug. 1, 1989, p. 135-141.

Advertised on:
8
1989
Journal
Astrophysical Journal
Number of authors
4
IAC number of authors
3
Citations
52
Refereed citations
42
Description
The evolution of the emission line ratios of a photoionized cloud described by standard BLR parameters which is exposed to a varying ionizing continuum is studied. The hardness of the ionizing distribution was varied by decoupling the UV increase from that of the X-ray component. After many tests using various ionizing distributions, it became apparent that the energy distribution must change in certain specific ways if Ly-alpha/C IV is to increase monotonically with f(1338 A) as in Fairall 9. A distribution composed of a varying 10 eV bump and a constant luminosity X-ray power law can successfully reproduce the observed Ly-alpha/C IV slope. This would be consistent with reported X-ray data only if the varying absorbing column density model were a valid explanation of its variability.
Type
Refereed
Active galactic nuclei
Seyfert galaxies

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