2005/08/29 by Sara L. Ellison, Lisa J. Kewley, Ellison, Sara L. +1
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0508627
Proceedings contribution for "The Fabulous Destiny of Galaxies; Bridging the Past and Present"
arxiv created 2005/08/29 · openalex publication_date 2005/08/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We calculate the oxygen abundances for ~45,000 star-forming galaxies selected from the SDSS using nine popular `strong-line' metallicity diagnostics. We find that individual galaxies can have metallicities which differ by factors of up to ~4, depending on the choice of abundance diagnostic. The resulting mass-metallicity relations subsequently exhibit significant offsets, with a range of 0.5 dex in metallicity at a given mass. This demonstrates that different metallicity diagnostics should not be used interchangeably for determining oxygen abundances. We also show that SDSS spectra are dominated by the central galactic component which introduces a noticeable aperture effect.