Weak interstellar lines in the visible spectrum of Zeta Ophiuchi.
Abstract
Interstellar absorption lines in the spectrum of 0ph have been investigated using a synthesis technique to superpose 31 high-dispersion spectrograms in the wavelength region A. The minimum detectable equivalent width is approximately 0.25 mA. Lines which have been observed for the first time in the spectrum of this star are Ca I A4226, Fe I AA3720 and 3860, and K I AA4044 and 4047. Using these data and assuming ionization equilibrium, a new evaluation of the electron density, hydrogen density, and elemental abundances is presented for the -15 km 1 cloud. With the direct measurement of both the Ca I and Ca ii column densities, the relative abundance computations are shown to be insensitive to the choice of radiation field and kinetic temperature. Subject headings: interstellar matter - stars, individual
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1974
- DOI:
- 10.1086/153132
- Bibcode:
- 1974ApJ...193...97S
- Keywords:
-
- Absorption Spectra;
- Abundance;
- Atomic Spectra;
- Interstellar Extinction;
- Line Spectra;
- Stellar Spectra;
- Electron Density (Concentration);
- Luminous Intensity;
- Oao 3;
- Satellite Observation;
- Spectral Line Width;
- Astrophysics