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arXiv · 1812.05812

Stellar population synthesis of galaxies with chemical evolution model

Shiyin Shen·Jun Yin
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Abstract

The derivation of accurate stellar populations of galaxies is a non-trivial task because of the well-known age-metallicity degeneracy. We aim to break this degeneracy by invoking a chemical evolution model(CEM) for isolated disk galaxy, where its metallicity enrichment history(MEH) is modelled to be tightly linked to its star formation history(SFH). Our CEM has been successfully tested on several local group dwarf galaxies whose SFHs and MEHs have been both independently measured from deep color-magnitude diagrams of individual stars. By introducing the CEM into the stellar population fitting algorithm as a prior, we expect that the SFH of galaxies could be better constrained.

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Shiyin Shen, Jun Yin. 2018-12-14. Stellar population synthesis of galaxies with chemical evolution model. https://doi.org/10.1017/s1743921319002758

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