Emission line ratios from H II regions in two nearby galaxies - NGC 7424 and M83
Abstract
Twenty-six H II regions in the two Sc galaxies M83 and NGC 7424 were observed, using the Wampler-Robinson image dissector scanner with a resolution of approximately 10 A. A reduction program was applied to the data to derive intensity-calibrated parameters for the H II regions. In particular, the forbidden O III/H-beta excitation parameter, and forbidden N II/H-alpha ratio were correlated with distance from the centers of the galaxies. The results are consistent with what is known about abundance gradients and star formation rates in galaxies. In particular, the data indicate that more metals are present in the galaxy (M83) with the greater surface brightness.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- May 1981
- DOI:
- 10.1093/mnras/195.2.353
- Bibcode:
- 1981MNRAS.195..353B
- Keywords:
-
- Astronomical Spectroscopy;
- Emission Spectra;
- Galactic Structure;
- H Ii Regions;
- Spiral Galaxies;
- Astronomical Catalogs;
- H Lines;
- Metals;
- Optical Thickness;
- Spectral Line Width;
- Star Formation Rate;
- Astrophysics