The Neutral Oxygen Spectrum. II. Pumping by Hydrogen Lyman- beta under the Optically Thin Condition: A First Application to the Classical Novae
Abstract
A calculation, employing a detailed model of neutral oxygen, is carried out to give fluorescent line intensities expected in a long-proposed photoexcitation by accidental resonance (PAR) process in which hydrogen Lyman-beta photo-excites the oxygen spectrum. The results pertain to the optically thin case but provide an upper limit to the fluorescent intensities which can be attained. They are applied to analyze line ratios involving the strong 8446 A line observed in classical novae during the diffusion-enhanced and Orion phases. Operation of the PAR process in the novae is verified. It is found that photoexcitation rates in the ejecta reach values greater than 0.1/sec, corresponding to hydrogen Lyman-beta radiation field intensities greater than 1250 ergs/cm/sec/sr.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1995
- DOI:
- 10.1086/175178
- Bibcode:
- 1995ApJ...439..346K
- Keywords:
-
- Energy Levels;
- Lyman Beta Radiation;
- Mathematical Models;
- Novae;
- Nuclear Pumping;
- Oxygen Spectra;
- Stellar Mass Ejection;
- Computation;
- Data Reduction;
- Electron Density (Concentration);
- Photoexcitation;
- Spectral Energy Distribution;
- Astrophysics;
- ATOMIC PROCESSES;
- STARS: NOVAE;
- CATACLYSMIC VARIABLES