The effect of intermediate-mass close binaries on the chemical evolution of globular clusters
The effect of intermediate-mass close binaries on the chemical evolution of globular clusters
复制标题
DOI：
10.1051/0004-6361/201118081
复制
发表时间：
2011-09
影响因子：
6.5
通讯作者：
D. Vanbeveren;N. Mennekens;J. Greve
中科院分区：
文献类型：
--
作者：
D. Vanbeveren;N. Mennekens;J. Greve
上下文中等质量单星渐近巨星分支（AGB）演化过程中的化学过程预测了球状星团中不同星族的大部分观测结果，但一些重要问题仍需进一步澄清。特别是，为了重现观察到的Na-O和Al-Mg的关系，在中等质量恒星的AGB阶段失去的化学富集气体必须与原始化学成分的物质混合。这件事的根源仍在争论中。此外，观测显示，相当一部分中等质量和大质量恒星是作为密近双星的组成部分诞生的。目标。我们研究了双星对球状星团化学演化的影响，以及对单星AGB方案工作所需的原始化学成分物质的起源的影响。方法.我们使用了一个人口合成代码，占二进制物理估计的数量和组成的物质返回到星际介质的人口的二进制。结果我们证明，一个显着的人口的中等质量的密近双星的质量损失结合单星AGB污染的情况下，可能有助于解释的化学性质的不同人口的恒星在球状星团。
Context. The chemical processes during the asymptotic giant branch (AGB) evolution of intermediate-mass single stars predict most of the observations of the different populations in globular clusters although some important questions still need to be further clarified. In particular, to reproduce the observed anticorrelations of Na-O and Al-Mg, chemically enriched gas lost during the AGB phase of intermediate-mass single stars must be mixed with matter with a pristine chemical composition. The source of this matter is still debated. Furthermore, observations reveal that a significant fraction of the intermediate-mass and massive stars are born as components of close binaries. Aims. We investigate the effects of binaries on the chemical evolution of globular clusters and on the origin of matter with a pristine chemical composition that is needed for the single-star AGB scenario to work. Methods. We used a population synthesis code that accounts for binary physics to estimate the amount and the composition of the matter returned to the interstellar medium of a population of binaries. Results. We demonstrate that the mass lost by a significant population of intermediate-mass close binaries in combination with the single-star AGB pollution scenario may help to explain the chemical properties of the different populations of stars in globular clusters.