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arXiv · 0910.1367

Globular clusters as laboratories for stellar evolution

M. Catelan·A. A. R. Valcarce·A. V. Sweigart
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Abstract

Globular clusters have long been considered the closest approximation to a physicist's laboratory in astrophysics, and as such a near-ideal laboratory for (low-mass) stellar evolution. However, recent observations have cast a shadow on this long-standing paradigm, suggesting the presence of multiple populations with widely different abundance patterns, and -- crucially -- with widely different helium abundances as well. In this review we discuss which features of the Hertzsprung-Russel diagram may be used as helium abundance indicators, and present an overview of available constraints on the helium abundance in globular clusters.

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M. Catelan, A. A. R. Valcarce, A. V. Sweigart. 2009-10-07. Globular clusters as laboratories for stellar evolution. https://doi.org/10.1017/s1743921309991153

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