低金属丰度下重元素丰度比分布弥散探究  

Investigation of the Scatter of Heavy Element Ratio at Low Metallicities

作　　者：周贵德[1] 

机构地区：[1]沧州师范学院物理与电子信息系,河北沧州061001

出　　处：《沧州师范学院学报》2013年第2期37-41,共5页Journal of Cangzhou Normal University

摘　　要：介绍了重元素核合成理论,利用对流模型计算了AGB星核合成产量随金属丰度的变化.发现在低金属丰度条件下的不同质量AGB星中存在的较大的内禀性质的中子辐照量弥散,可以自然地解释观测到的重元素丰度比[ls/Fe]和[hs/Fe]随着金属丰度的降低而出现的离散现象.根据AGB星的重叠因子与其初始质量的变化关系,我们可以推测:较大的[ls/Fe]和[hs/Fe]数值对应着初始质量较小的AGB星,而小的[ls/Fe]和[hs/Fe]数值则对应着具有较大初始质量的AGB星.The theory of nucleosynthesis of heavy element is introduced. The production of AGB nucleosynthesis is caculated at different metallicities by using the convective model. It is found that based on Zijlstra＇s initial＇-final mass relations, the scatter of heavy element ratio, i.e. [ls/Fe] and [hs/Fe] at low metallicities can be explained naturally by varying the initial mass of the low-mass AGB stars. According to the relationship between the changes of overlapping ele- ment and initial quality AGB star, we can speculate that the larger values of [ls/Fe] and [hs/Fe] corresponds to the lighter-mass of AGB stars and the lighter values of [ls/Fe] and [hs/Fe] correspond to the larger mass of AGB stars.

关 键 词：AGB星 核合成 S-过程 

分 类 号：P144[天文地球—天体物理]