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FeII/MgII, [Fe/Mg] Ratios and High-z Quasars

Kirk Korista·Nalaka Kodituwakku·Michael Corbin·Wolfram Freudling
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Abstract

It has been suggested in the literature that the (Fe/alpha) abundance ratio may be used as a chronometer, due to a delay in this ratio reaching its solar value as predicted by galactic chemical evolution models. Using grids of photoionization models along a sequence of the (Fe/Mg) abundance ratio vs.\ metallicity with time in a giant elliptical starburst scenario, we investigate the relationship between the (Fe/Mg) abundance ratio and the FeII/MgII emission line flux ratio under the assumption that these lines originate in photoionized clouds within the broad emission line regions of quasars.

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Kirk Korista, Nalaka Kodituwakku, Michael Corbin, Wolfram Freudling. 2003-11-05. FeII/MgII, [Fe/Mg] Ratios and High-z Quasars. https://arxiv.org/abs/astro-ph/0311126

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