Emission lines of Mg II and Ca II in planetary nebulae
Journal Article
·
· Astrophysics (Engl. Transl.); (United States)
Conditions of excitation of the emission resonance lines of ionized magnesium and calcium in planetary nebulae are analyzed. The allowed lines are excited by the same mechanism as the forbidden lines and not by ordinary fluorescence. An emission line lambda 2800 Mg II of reasonable strength can be observed in the spectra of planetary nebulae of medium excitation, but not in highly excited nebulae. The absence of the H and K emission lines of Ca II in the spectra results from their expected intensity which is 3 to 4 orders of magnitude lower than the intensity of the line lambda 2800 Mg II or H(beta) of hydrogen.
- Research Organization:
- Biurakanskaia Astrofizicheskaia Observatoriia, Yerevan, Armenian SSR
- OSTI ID:
- 6806010
- Journal Information:
- Astrophysics (Engl. Transl.); (United States), Journal Name: Astrophysics (Engl. Transl.); (United States) Vol. 15:3; ISSN ATPYA
- Country of Publication:
- United States
- Language:
- English
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