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arXiv · 1704.07382

Yonsei evolutionary population synthesis (YEPS). II. Spectro-photometric evolution of helium-enhanced stellar populations

Chul Chung·Suk-Jin Yoon·Young-Wook Lee
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Abstract

The discovery of multiple stellar populations in Milky Way globular clusters (GCs) has stimulated various follow-up studies on helium-enhanced stellar populations. Here we present the evolutionary population synthesis models for the spectro-photometric evolution of simple stellar populations (SSPs) with varying initial helium abundance ($Y_{\rm ini}$). We show that $Y_{\rm ini}$ brings about {dramatic} changes in spectro-photometric properties of SSPs. Like the normal-helium SSPs, the integrated spectro-photometric evolution of helium-enhanced SSPs is also dependent on metallicity and age for a given $Y_{\rm ini}$. {We discuss the implications and prospects for the helium-enhanced populations in relation to the second-generation populations found in the Milky Way GCs.} All of the models are available at \url{http://web.yonsei.ac.kr/cosmic/data/YEPS.htm}.

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Chul Chung, Suk-Jin Yoon, Young-Wook Lee. 2017-04-24. Yonsei evolutionary population synthesis (YEPS). II. Spectro-photometric evolution of helium-enhanced stellar populations. https://doi.org/10.3847/1538-4357/aa6f19

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