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Early star formation traced by the highest redshift quasars

R. Maiolino·Y. Juarez·R. Mujica·N. Nagar·E. Oliva
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Abstract

The iron abundance relative to alpha-elements in the circumnuclear region of quasars is regarded as a clock of the star formation history and, more specifically, of the enrichment by SNIa. We investigate the iron abundance in a sample of 22 quasars in the redshift range 3.0 6. We also detect a population of weak iron emitters at z~4.5, which are possibly hosted in systems that evolved more slowly. Alternatively, the trend of the FeII/MgII ratio at high redshift may reflect significantly different physical conditions of the circumnuclear gas in such high redshift quasars.

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R. Maiolino, Y. Juarez, R. Mujica, N. Nagar, E. Oliva. 2003-09-08. Early star formation traced by the highest redshift quasars. https://doi.org/10.1086/379600

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