Theoretical models for H II regions. II - The extragalactic H II region abundance sequence

Details Theoretical models for H II regions. II - The extragalactic H II region abundance sequence Theoretical models for H II regions. II - The extragalactic H II region abundance sequence

Aug 1986

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1986apj...307..431d&link_type=abstract

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 307, Aug. 15, 1986, p. 431-440.

Astronomy and Astrophysics

Astrophysics

211

Abundance, Cosmochemistry, H Ii Regions, Nebulae, Astronomical Models, Astronomical Spectroscopy, Emission Spectra, Galactic Evolution, Metallicity

Scientific paper

With the aid of an extensive homogeneous grid of theoretical photoionization models (Evans and Dopita, 1985), a multiline fit to the observed emission-line spectral sequence of extragalactic H II regions is generated. It is possible to produce an excellent fit between the (rather narrow) emission-line ratio sequences that are observed and the theoretical sequences, provided that the average ionization parameter is strongly coupled with metallicity, and provided that nitrogen is a product of secondary nucleosynthesis. Using this theoretical sequence of H II region models, the semiempirical abundance diagnostic ratios used by Alloin et al. (1979), Pagel et al. (1979), and McCall et al. (1985) are recalculated, and new abundance of diagnostic ratios are generated. It is found that the correlation between ionization parameter and abundance has the effect of changing the previous abundance calibration toward lower abundances, particularly for the most metal-rich H II regions. Finally, a new technique to derive abundances from H II region spectra is presented.

Affiliated with

Also associated with

No associations

Rating

Theoretical models for H II regions. II - The extragalactic H II region abundance sequence 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 Theoretical models for H II regions. II - The extragalactic H II region abundance sequence, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Theoretical models for H II regions. II - The extragalactic H II region abundance sequence will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-891841