Other
Scientific paper
Jul 1983
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1983mnras.204...53s&link_type=abstract
Monthly Notices of the Royal Astronomical Society (ISSN 0035-8711), vol. 204, July 1983, p. 53-112.
Other
731
Abundance, Interstellar Matter, Milky Way Galaxy, Carbon, Electron Density (Concentration), Electron Energy, H Ii Regions, Helium Ions, Hydrogen Ions, Metallicity, Neon, Nitrogen, Nuclear Fusion, Oxygen, Stellar Temperature, Sulfur, Temperature Gradients
Scientific paper
Chemical abundances in a large and representative sample of galactic H II regions covering a wide range in galactocentric radius RG were measured using radio and optical spectroscopy. Accurate electron temperatures in 67 H II regions spanning the range RG = 3.5-13.7 kpc were determined using radio recombination lines and these temperatures were applied to optical spectra of 33 of the same H II regions in order to determine the abundances of O, N, S, Ne, Ar, and He(+). Among other results, it is found that some H II regions have electron temperatures below 5000 K and that the radio-determined electron temperatures agree well with those obtained from the optical line ratios, in the light of standard models of H II regions. A gradient of H II region electron temperature with distance from the galactic center is found which equals +433 + or - 40 K/kpc, while the oxygen abundance gradient is -0.07 + or - 0.015 dex/kpc. The nitrogen abundance gradient is similar to that of oxygen, -0.09 + or 0.015 dex/kpc, while the sulfur abundance gradient (-0.01 + or - 0.02 dex/kpc) is significantly flatter than that of oxygen. No significant gradient in He(+)/H(+) is detected. In addition, evidence indicates that the abundance gradients may be steeper over the inner regions of the galactic disk.
Danks Anthony C.
McGee Richard X.
Newton Lynette M.
Pottasch Stuart R.
Shaver Peter A.
No associations
LandOfFree
The galactic abundance gradient does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The galactic abundance gradient, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The galactic abundance gradient will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1628389