[O iii]/[N ii] as an abundance indicator at high redshift
نویسندگان
چکیده
Among ‘empirical’ methods of estimating oxygen abundances in extragalactic H ii 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])/Hβ and N2 ≡ [N ii] λ6583/Hα, particularly when applied to star-forming galaxies at high redshifts.
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