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The Chemical Evolution of Galaxies by Successive Starbursts

T. Contini·R. Coziol·S. Considere·E. Davoust·R. E. Carlos Reyes
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Abstract

We propose an evolutionary scenario by successive bursts of star formation to reproduce the chemical properties of massive nearby Starburst Nucleus Galaxies (SBNGs). The N/O abundance ratios in SBNGs are 0.2 dex higher than in normal HII regions observed in the disks of late-type spirals. The variation of the N/O ratio as a function of metallicity follows a "primary + secondary" relation, but the increase of nitrogen does not appear as a continuous process. Assuming that nitrogen is produced by intermediate-mass stars, we show that our observations are consistent with a model where the bulk of nitrogen in SBNGs was formed during past sequences of bursts of star formation which probably started 2 or 3 Gyrs in the past.

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T. Contini, R. Coziol, S. Considere, E. Davoust, R. E. Carlos Reyes. 1999-05-27. The Chemical Evolution of Galaxies by Successive Starbursts. https://arxiv.org/abs/astro-ph/9905359

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