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On star formation and chemical evolution in the Galactic disc

L. Portinari·C. Chiosi
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Abstract

The abundance gradients and the radial gas profile of the Galactic disc are analysed by means of a model for the chemical evolution of galaxies. As one of the major uncertainties in models for galaxy evolution is the star formation (SF) process, various SF laws are considered,to assess the response of model predictions to the different assumptions. Only some SF laws are successful in reproducing the metallicity gradient, and only if combined with a suitable infall timescale increasing outward (inside-out formation scenario). Still, it is difficult to reproduce at the same time also the observed gas distribution; we therefore suggest further improvements for the models.

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L. Portinari, C. Chiosi. 1999-08-30. On star formation and chemical evolution in the Galactic disc. https://arxiv.org/abs/astro-ph/9908326

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