Astronomy and Astrophysics – Astrophysics
Scientific paper
Dec 1981
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1981apj...251...10l&link_type=abstract
Astrophysical Journal, Part 1, vol. 251, Dec. 1, 1981, p. 10-14. Research supported by the California Space Institute
Astronomy and Astrophysics
Astrophysics
8
Atomic Spectra, Helium Atoms, Infrared Spectra, Optical Thickness, Seyfert Galaxies, Astronomical Catalogs, Cosmic Dust, Electron Density (Concentration), Electron Energy, H Lines, Interstellar Extinction, Quasars
Scientific paper
The observed He 10830 A/5876 A ratio found in He 10830 line flux measurements for the cases of the Seyfert 1 galaxies NGC 3516, 4151, 7469, and Mrk 509, and for the Seyfert 2 galaxy NGC 1068, is smaller than predicted for a high-density and optically thin gas in the case of the four Seyfert 1 galaxies. This is seen as a consequence of optical depth effects in the 10830 A transition with tau(10830 A) being greater than about 250. The observed line ratio for NGC 1068 is smaller, and the intrinsic ratio in this galaxy is probably similar to the Seyfert 1 galaxies but more highly reddened by dust. Although the assumed intrinsic value could be explained by very low electron temperatures and densities for that object, it is suggested that a large 10830 A optical depth is also required.
Levan Paul D.
Puetter Richard C.
Rudy Richard J.
Smith Harding E.
Willner Steve P.
No associations
LandOfFree
He I lambda 10830 observations of five Seyfert galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with He I lambda 10830 observations of five Seyfert galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and He I lambda 10830 observations of five Seyfert galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1260586