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[O III]/[N II] as an Abundance Indicator at High Redshift

Max Pettini·Bernard E J Pagel
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Abstract

Among `empirical' methods of estimating oxygen abundances in extragalactic HII regions, the use of the ratio of nebular lines of [O III] and [N II], first introduced by Alloin et al. in 1979, is reappraised with modern calibration data and shown to have certain advantages over R23 = ([O II] + [O III])/Hbeta and N2 = [NII] 6583/Halpha, particularly when applied to star-forming galaxies at high redshifts.

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Max Pettini, Bernard E J Pagel. 2004-01-08. [O III]/[N II] as an Abundance Indicator at High Redshift. https://doi.org/10.1111/j.1365-2966.2004.07591.x

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