【摘要】 首先考虑到随前身星质量增加Ⅱ型超新星爆发α元素的产量并不单调增加,从而导致Ⅱ型超新星所污染的星际气体的α元素丰度出现反转的因素,将贫金属星Ba的观测丰度分为2支,其中i支元素丰度产生于较低质量超新星,y支元素丰度产生于较高质量超新星,采用FM2004的Ⅱ型超新星爆发Mg元素的产量,利用Tsujimoto提出的方法,根据观测到的极贫金属星Ba和Mg丰度数值计算各种质量超新星r过程的产量,得出星系中r过程元素核合成的主要质量区间.然后,根据得到的不同质量Ⅱ型超新星r过程的产量关系,改进Fields等所提出的方法,解释观测到的贫金属星中子俘获元素的弥散性;另外,还根据3成份(晕、厚、薄盘)多相模型(气体、分子云、大小质量恒星以及剩余物质),利用所得到的产量计算了r过程元素的均匀化学演化.更多还原

【Abstract】 The factor that the mass of ejected α-element does not always increase with the increasing of progenitor’s mass,so α-element in the galactic interstellar medium(ISM) decrease at massive progenitor remnants is considered.The observed abundances of Ba are divided into two branches i and y.Ibranch is the one produced in the minor typeⅡsupernovae(SNⅡ) and y-branch is the one produced in the massive SNⅡ.So Mg yields of FM2004 and the method of Tsujimoto are used,then main mass range of r-process are obtained.According to the obtained function of r-process yields and SN Ⅱ progenitor mass,the methods presented by fields are improved,scatter of n-capture elements in metal poor stars are explained.The model named three-zone multiphase model are used in order to study the chemical evolution of the Galaxy.更多还原