Metallicities of 0.3 z < 1.0 Galaxies in the GOODS‐North Field

We measure nebular oxygen abundances for 204 emission-line galaxies with redshifts 0. 3<z<1. 0 in the Great Observatories Origins Deep Survey North (GOODS-N) field using spectra from the Team Keck Redshift Survey (TKRS). We also provide an updated analytic prescription for estimating oxygen abundances using the traditional strong emission line ratio, R₂₃, based on the photoionization models of Kewley & Dopita (2003). We include an analytic formula for very crude metallicity estimates using the NII6584/Halpha ratio. Oxygen abundances for GOODS-N galaxies range from 8. 2< 12+log (O/H) < 9. 1 corresponding to metallicities between 0. 3 and 2. 5 times the solar value. This sample of galaxies exhibits a correlation between rest-frame blue luminosity and gas-phase metallicity (i. e. , an L-Z relation), consistent with L-Z correlations of previously-studied intermediate-redshift samples. The zero point of the L-Z relation evolves with redshift in the sense that galaxies of a given luminosity become more metal poor at higher redshift. Galaxies in luminosity bins -18. 5<MB<-21. 5 exhibit a decrease in average oxygen abundance by 0. 140. 05 dex from z=0 to z=1. This rate of metal enrichment means that 280. 07% of metals in local galaxies have been synthesized since z=1, in reasonable agreement with the predictions based on published star formation rate densities which show that ~38% of stars in the universe have formed during the same interval. (Abridged)