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Dwarf Spheroidals and the Evolution of Not-Too-Old Population II Stars

V. Castellani·S. Degl'Innocenti
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Abstract

Previous evolutionary computations concerning stars with masses in the range of the ``Red Giants Transition Phase'' are extended to lower metallicities. Clusters isochrones for two values of the metallicity Z (Z=10E-4, 4E-4) and for ages down to 1 billion years are presented, discussing selected evolutionary features characterizing the structure of the stars during both H or He burning phases. One finds that clusters with Z about equal to 1E-4 an age around 1-2 billion years could be characterized by the occurrence of anomalous He burning variables at a luminosity of the order of LogL= 2.0-2.2 (in solar units).

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V. Castellani, S. Degl'Innocenti. 1994-06-22. Dwarf Spheroidals and the Evolution of Not-Too-Old Population II Stars. https://arxiv.org/abs/astro-ph/9406058

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