贫金属星的表面丰度与慢中子俘获过程

Abundances of Metal-Poor Stars and Slow Neutron-Capture Progress

在不依赖于特定恒星模型的前提下 ,采用参数化热脉冲模型 ,对三颗铅星的表面丰度进行了拟合计算 .结果表明 ,无论是否考虑分叉道的影响 ,结果均能很好地重现观测数据 .另外 ,铅星与非铅星的模型参量对比显示 ,铅星的平均中子辐照量远大于非铅星 ,而其挖掘程度明显小于非铅星 .这说明尽管参数化热脉冲模型过于简单 。

We apply the parametric model to fit the surface abundances of three lead rich stars (HD187861, HD196944 and HD224959) without adopting any specific stellar model. It shows that the calculated result can fit the observed data well whether the reaction branchings are taken into account or not. Besides, by the comparison of the model parameters of the three lead rich stars with those of two very metal poor stars (LP625 44 and LP706 7), we find out that the average neutron exposure of the former is larger than that of the latter, but the dredge up extent is smaller. We come to the conclusion that the parametric model is significant of constraints on the stellar model, though it is very simple.