On VI absorption in interstellar cloud surfaces?
Abstract
The velocity profiles of O VI absorption lines of 24 stars, observed in early Copernicus surveys, have been compared with the line profiles of Si III (1206.51 A) and N II (1083.99 A). The velocity structures of the O VI lines appear to be correlated with those of the material in the lower ionization stages. It is argued that the O VI absorption arises in the coronal gas of the conductive interface between hot gas, responsible for extended, soft X-ray emission, and cooler interstellar clouds. The velocity broadening of both sets of lines is attributed to motions of the cloud surfaces induced by pressure fluctuations in the interstellar medium.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1979
- DOI:
- 10.1086/157305
- Bibcode:
- 1979ApJ...232..467C
- Keywords:
-
- Absorption Spectra;
- Astronomical Spectroscopy;
- Interstellar Gas;
- Oxygen Spectra;
- Correlation Coefficients;
- Hydrogen Clouds;
- Line Spectra;
- Oao 3;
- Velocity Distribution;
- Astrophysics;
- Interstellar Clouds:UV Spectra;
- Interstellar Clouds:Velocities