Intermediate-age metal deficient stellar populations: the case of metallicity Z=0.00001 S.Cassisi1,2, M. Castellani3, and V.Castellani1,4
نویسندگان
چکیده
We investigate the evolution of metal deficient stars, presentingH-burning isochrones covering cluster ages from800 Myr to 7 Gyr. Evolutionary evidences for selection effects in the metallicity distribution of very metal poor H-burning red giants are reported. The evolution of stars during central and shell He burning is further investigated, discussing the occurrence of He burning pulsators as a function of cluster age.
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