Abundances in five nearby galactic HII regions from infrard forbidden lines.
Abstract
Airborne measurements of the Ar II (6.99 micron) and S II (18.7) micron lines for five compact H II regions in the solar neighborhood are presented, as well as 2-4 micron and 8-13 micron spectroscopy where available. From these data and radio data, lower limits to the elemental abundances of Ar, Ne, and S are deduced. Some of these H II regions suffer substantial nebular extinction, and some are extended. After correcting for beam size effects an extinction, it is found that four of the objects are consistent with standard abundances, within the uncertainties of correcting for unobserved ionization states. A Perseus arm object, S156, is apparently overabundant in sulfur.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1982
- DOI:
- 10.1086/160406
- Bibcode:
- 1982ApJ...262..153H
- Keywords:
-
- Galactic Structure;
- H Ii Regions;
- Infrared Spectra;
- Nebulae;
- Abundance;
- Argon;
- Emission Spectra;
- Interstellar Extinction;
- Line Spectra;
- Neon;
- Sulfur;
- Astrophysics