IUE observations of X-ray emitting Seyfert galaxies.
Abstract
International Ultraviolet Explorer observations were made of the X-ray emitting Seyfert galaxies NGC 3783, Mkn 506, Mkn 279, 3C 390.3 and NGC 5548. The continuum intensities lead to estimates of reddening consistent with local (galactic) extinction; there is no evidence for any reddening intrinsic to the source. The (rest-frame) ratios log F lambda (1450 A) vs log W lambda (C IV) deduced from this sample indicate when combined with similar observations of high-z Seyferts, a correlation similar to that observed in OSOs. Repeated observations of NGC 3783 revealed continuum variability by a factor 3 in seven months, the spectrum becoming harder as the flux density increases. The low degree of extinction observed in this source in November 1978 contrasts strongly with the high degree of X-ray absorption detected by the Ariol V satellite three weeks earlier.
- Publication:
-
Ultraviolet observations of Quasars
- Pub Date:
- April 1980
- Bibcode:
- 1980ESASP.157..289B
- Keywords:
-
- Astronomy;
- Iue;
- Seyfert Galaxies;
- Ultraviolet Astronomy;
- X Ray Sources;
- Ariel 5 Satellite;
- Continuous Spectra;
- Emission Spectra;
- Interstellar Extinction;
- Lyman Alpha Radiation;
- Variability