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arXiv · 1508.05222

Direct determination of oxygen abundances in line emitting star-forming galaxies at intermediate redshift

José M. Pérez·Carlos Hoyos·Ángeles I. Díaz·David C. Koo·Christopher N. Willmer
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Abstract

We present a sample of 22 blue ($(B-V)_{AB}<0.45$), luminous ($M_{B,AB}<-18.9$), metal-poor galaxies in the $0.69<z<0.88$ redshift range, selected from the DEEP2 galaxy redshift survey. Their spectra contain the $[OIII]\lambda4363$ auroral line, the $[OII]λ\lambda3726,3729$ doublet and the strong nebular $[OIII]λλ4959,5007$ emission lines. The ionised gas-phase oxygen abundances of these galaxies lie between $7.62<12+\log O/H < 8.19$, i.e. between $1/10 Z_{\odot}$ and $1/3 Z_{\odot}$. We find that galaxies in our sample have comparable metallicities to other intermediate-redshift samples, but are more metal poor than local systems of similar B-band luminosities and star formation activity. The galaxies here show similar properties to the "green peas" discovered at $z\simeq 0.2 - 0.3$ though our galaxies tend to be slightly less luminous.

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José M. Pérez, Carlos Hoyos, Ángeles I. Díaz, David C. Koo, Christopher N. Willmer. 2015-08-21. Direct determination of oxygen abundances in line emitting star-forming galaxies at intermediate redshift. https://doi.org/10.1093/mnras%2Fstv1949

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