The spectrum of PG 1700+518.
Abstract
Observations of PG 1700 + 518 show that this bright quasar has a very rich Fe II emission spectrum. In addition, there is a broad dip in spectral intensity to the blue of Mg II lambda 2800. It is argued that this dip is due to detached Mg II lambda 2800 absorption rather than to a gap between Fe II emission lines. Fe II transitions from 8 eV levels seem to be present in the spectrum. Also present are weak multiplets with the same upper levels as the strong optical multiplets 27 and 42. These observational data support the belief that the resonance lines of Fe II are optically thick and that the 8 eV levels are populated, presumably by fluorescence. Forbidden lines are very weak or absent in PG 1700 + 518.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1985
- DOI:
- 10.1086/163460
- Bibcode:
- 1985ApJ...296..416W
- Keywords:
-
- Astronomical Spectroscopy;
- Emission Spectra;
- Quasars;
- Spectrum Analysis;
- Absorption Spectra;
- Fine Structure;
- Iron;
- Line Spectra;
- Magnesium;
- Optical Thickness;
- Resonance Lines;
- Astrophysics