H I absorption in NGC 4945.
Abstract
The NGC 4945, a ninth-magnitude southern galaxy orientated almost edge-on to the line of sight, is of particular interest because 18-cm OH and 6-cm H2CO absorption has been detected in the galaxy's molecular clouds that overlie the small-diameter radio source located near the nucleus. In reporting the detection of the OH absorption, Whiteoak and Gardener (1974) suggested that the HI profile in the direction of the nucleus was affected by HI absorption. In the present paper, a study of the HI distribution, which substantiates this hypothesis, is described.
- Publication:
-
Publications of the Astronomical Society of Australia
- Pub Date:
- September 1977
- DOI:
- Bibcode:
- 1976PASA....3...71W
- Keywords:
-
- Absorption Spectra;
- Emission Spectra;
- Galactic Nuclei;
- Galaxies;
- H Lines;
- Hydrogen Clouds;
- Line Spectra;
- Atomic Energy Levels;
- Formaldehyde;
- Galactic Radio Waves;
- Hydrogen Atoms;
- Hydroxyl Emission;
- Molecular Gases;
- Spatial Distribution;
- Astrophysics