2007/07/19 by L. S. Pilyugin, T. X. Thuan · 1 citation
Physics and Astronomy · #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/521597
39 pages, 10 figures, 4 tables, accepted for publication in the Astrophysical Journal
arxiv created 2007/07/19 · openalex publication_date 2007/11/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We have derived the oxygen abundance for a sample of nearby galaxies in Data Release 5 of the Sloan Digital Sky Survey (SDSS) that possess at least two independent spectra of one or several H II regions with a detected [O III] λ4363 auroral line. Since, for nearby galaxies, the [O II] λ3727 nebular line is out of the observed wavelength range, we propose a method to derive (O/H) ff abundances using the classic T e method coupled with the flux-flux (ff) relation. (O/H) 7325 abundances have also been determined, based on the [O II] λλ7320, 7330 line intensities and using a small modification of the standard T e method. The (O/H) ff and (O/H) 7325 abundances have been derived with both the one- and two-dimensional t 2 - t 3 relations. It was found that the (O/H) ff abundances derived with the parametric two-dimensional t 2 - t 3 relation are the most reliable. Oxygen abundances have been determined in 29 nearby galaxies on the basis of 84 individual abundance determinations in H II regions. Because of our selection methods, the metallicity of our galaxies lies in the narrow range 8.2 ≲ 12 + log(O/H) ≲ 8.4. The radial distribution of oxygen abundances in the disk of the spiral galaxy NGC 4490 is determined for the first time.