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arXiv · 0706.0238

Nitrogen Production in Starburst Galaxies Detected by GALEX

Ryan P. Mallery·Lisa Kewley·R. Michael Rich·Samir Salim·Stephane Charlot·Christy Tremonti·Mark Seibert·Todd Small·Ted Wyder·Tom A. Barlow·Karl Forster·Peter G. Friedman·D. Christopher Martin·Patrick Morrissey·Susan G. Neff·David Schiminovich·Luciana Bianchi·Jose Donas·Timothy Heckman·Young-Wook Lee·Barry F. Madore·Bruno Milliard·Alex S. Szalay·Barry Y. Welsh·Suk Young Yi
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Abstract

We investigate the production of nitrogen in star forming galaxies with ultraviolet (UV) radiation detected by the Galaxy Evolution Explorer Satellite (GALEX). We use a sample of 8,745 GALEX emission line galaxies matched to the Sloan Digital Sky Survey (SDSS) spectroscopic sample. We derive both gas-phase oxygen and nitrogen abundances for the sample, and apply stellar population synthesis models to derive stellar masses and star formation histories of the galaxies. We compare oxygen abundances derived using three different diagnostics. We derive the specific star formation rates of the galaxies by modeling the 7-band GALEX+SDSS photometry. We find that galaxies that have log SFR/M$_*$ > -10.0 typically have values of log N/O ~0.05 dex less than galaxies with log SFR/M$_*$ < -10.0 and similar oxygen abundances.

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Ryan P. Mallery, Lisa Kewley, R. Michael Rich, Samir Salim, Stephane Charlot, Christy Tremonti, Mark Seibert, Todd Small, Ted Wyder, Tom A. Barlow, Karl Forster, Peter G. Friedman, D. Christopher Martin, Patrick Morrissey, Susan G. Neff, David Schiminovich, Luciana Bianchi, Jose Donas, Timothy Heckman, Young-Wook Lee, Barry F. Madore, Bruno Milliard, Alex S. Szalay, Barry Y. Welsh, Suk Young Yi. 2007-06-29. Nitrogen Production in Starburst Galaxies Detected by GALEX. https://doi.org/10.1086/518833

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