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Chemo-spectrophotometric evolution of spiral galaxies: III. Abundance and colour gradients in discs

N. Prantzos·S. Boissier
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Abstract

We study the relations between luminosity and chemical abundance profiles of spiral galaxies, using detailed models for the chemical and spectro-photometric evolution of galactic discs. The models are ``calibrated'' on the Milky Way disc and are successfully extended to other discs with the help of simple ``scaling'' relations, obtained in the framework of semi-analytic models of galaxy formation. We find that our models exhibit oxygen abundance gradients that increase in absolute value with decreasing disc luminosity (when expressed in dex/kpc) and are independent of disc luminosity (when expressed in dex/scalelength), both in agreement with observations. We notice an important strong correlation between abundance gradient and disc scalelength. These results support the idea of ``homologuous evolution'' of galactic discs.

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N. Prantzos, S. Boissier. 1999-11-07. Chemo-spectrophotometric evolution of spiral galaxies: III. Abundance and colour gradients in discs. https://doi.org/10.1046/j.1365-8711.2000.03228.x

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