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Two-component model for the chemical evolution of the Galactic disk

R. X. Chang·J. L. Hou·C. G. Shu·C. Q. Fu
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Abstract

In the present paper, we introduce a two-component model of the Galactic disk to investigate its chemical evolution. The formation of the thick and thin disks occur in two main accretion episodes with both infall rates to be Gaussian. Both the pre-thin and post-thin scenarios for the formation of the Galactic disk are considered. The best-fitting is obtained through $χ^2$-test between the models and the new observed metallicity distribution function of G dwarfs in the solar neighbourhood (Hou et al 1998). Our results show that post-thin disk scenario for the formation of the Galactic disk should be preferred. Still, other comparison between model predictions and observations are given.

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R. X. Chang, J. L. Hou, C. G. Shu, C. Q. Fu. 1999-03-22. Two-component model for the chemical evolution of the Galactic disk. https://arxiv.org/abs/astro-ph/9903317

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