Effects of α-Enhancement on Stellar Evolution
作者： Jian-Po Guo , Feng-Hui Zhang , Xue-Fei Chen , Zhan-Wen Han
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摘要: Using Eggleton's code, we systematically show the differences in stellar evolution between results based on scaled-solar mixture and a-enhanced metal mixture. As input, OPAL high temperature opacities are used for log(T/K) > 4.00, new Wichita State low opacities, <= 4.00. Our calculations cover star masses ranging from 0.25 to 80.0 M(circle dot), spaced at Delta log M = 0.10 or 0.05. The values of metallicities Z 0.0001, 0.0003, 0.001, 0.004, 0.01, 0.02, 0.03, 0.04, 0.06, 0.08 0.10. For a given Z, initial hydrogen mass fraction is by X 0.76 - 3.0Z. We that alpha-enhancement can raise effective luminosity, reduce evolutionary age. Compared with some previous work, effects more obviously demonstrated our calculations.
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