考虑时间延迟后较重r-过程元素的化学演化  

Chemical Evolution of Heavy r-Process Elements Considered the Time Delay

作　　者：周晓静[1] 赵国晴[1] 谷云高[1] 张波[2] 

机构地区：[1]邯郸学院物理与电气工程系,河北邯郸056005 [2]河北师范大学物理科学与信息工程学院,河北石家庄050016

出　　处：《河北大学学报（自然科学版）》2010年第4期365-370,共6页Journal of Hebei University(Natural Science Edition)

基　　金：国家自然科学基金资助项目（10673002）

摘　　要：考虑有效产生r-过程（快中子俘获过程）元素的Ⅱ型超新星延迟爆发的因素,大体上经过10次大质量Ⅱ型超新星（M〉35 M⊙）先爆发后,产生r-过程元素的Ⅱ型超新星（M=（28~35）M⊙）才开始爆发.从星系化学演化角度看,r-过程元素的主要来源为较大质量Ⅱ型超新星（M=（28~35）M⊙）.Ⅱ型超新星占Ⅱ型超新星总数的4%.核合成区域内种子核和中子源主要来自恒星自身的核反应.经计算得到星系晕中较重的r-过程元素Eu,Ba,Ce,La,Nd,Pr,Sm等元素丰度的离散情况及其化学演化.Considering the time delay between two supernovae events,the typeⅡsupernovae（M=（28—35） M⊙）which produced r-process broke out after the typeⅡsupernovae（M35 M⊙） done ten times.Our conclusion is that the r-process elements are mainly produced in a small fraction of the type Ⅱ supernovae（M=（28—35）M⊙）.The typeⅡsupernovae which produce heavy r-process elements originate from a small fraction 4% of all typeⅡsupernovae stars.The nucleus of theseed and neutron source in the nucleosynthesis sites were produced in nuclear reaction of the stellar themselves.The abundance scatter of Eu,Ba,Ce,La,Nd,Pr,Sm versus was calculated.The galactic chemical evolution of heavy elements from Ba to Eu was obtained.

关 键 词：Ⅱ型超新星 r-过程核合成的主要场所 延迟爆发 丰度离散 星系化学演化 

分 类 号：P142.9[天文地球—天体物理]