标题： 长寿命球状星团恒星的演化。 II. 作为球状星团年龄和金属丰度函数的渐近巨星分支上的钠丰度变化 显示英文标题

标题： Evolution of long-lived globular cluster stars. II. Sodium abundance variations on the asymptotic giant branch as a function of globular cluster age and metallicity

摘要： 球状星团中的长寿命恒星在化学成分上与其晕族恒星的对应物表现出特异性。特别是，富钠恒星被确认属于一个第二代恒星群体，这些恒星诞生于被第一代恒星氢燃烧产物污染过的星团物质。它们在色星图不同位置的存在和数量为自富集情景提供了重要的限制条件。特别是在渐近巨星支（AGB）上，贫钠与富钠恒星的比例最近被发现从一个星团到另一个星团之间存在强烈变化，而在红巨星支（RGB）上则相对恒定。我们在快速旋转大质量恒星自富集场景的框架内，研究了年龄和金属丰度对AGB上理论钠分布的影响。 显示英文摘要

摘要： Long-lived stars in GCs exhibit chemical peculiarities with respect to their halo counterparts. In particular, Na-enriched stars are identified as belonging to a 2d stellar population born from cluster material contaminated by the H-burning ashes of a 1st stellar population. Their presence and numbers in different locations of the CMDs provide important constraints on the self-enrichment scenarios. In particular, the ratio of Na-poor to Na-rich stars on the AGB has recently been found to vary strongly from cluster to cluster, while it is relatively constant on the RGB. We investigate the impact of both age and metallicity on the theoretical Na spread along the AGB within the framework of the fast rotating massive stars scenario for GC self-enrichment. (tb continued)