内转换效应在稀土区丰中子新核素鉴别中的应用  

Internal Conversion Effect Applications in Identifying New Neutron-Rich Nuclides in the Rare-Earth Region

作　　者：张学谦[1] 袁双贵[1] 杨维凡[1] 李宗伟[1] 牟万统[1] 于暹 罗亦孝[1] 郭天瑞[1] 

机构地区：[1]中国科学院近代物理研究所,兰州730000

出　　处：《高能物理与核物理》1997年第3期201-204,共4页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金;中国科学院八五重大项目双重资助.

摘　　要：用14 MeV 中子轰击天然镱靶,通过^(176)Yb(n,2p)反应产生了新核素^(175)Er 的活性.由于丰中子核^(175)Er 衰变γ跃迁有较大的内转换系数,因而伴随其衰变产生了较强子核 Tm 的特征 X 射线,因此,本工作借助于 X—γ—t,γ—γ—t符合测量技术并结合对反应道的分析,成功地从复杂反应产物中鉴别出稀土新丰中子同位素^(175)Er 的活性,并首次建议了该核素的部分衰变纲图.The new neutron-rich isotope ^(175)Er activity was produced via the reaction ^(176)Yb(n,2p) by 14 MeV neutron irradiation of natural ytterbium metals.When nuclide ^(175)Er decayed to its daughter nuclide ^(175)Tm,Tm characteristic X rays would be emitted with a certain ratio due to the internal conversions.So X-γ and γ-γ coincidence measurements were employed to successfully identify the neutron-rich isotope activities of rare-earth element from other rare-earth reaction products.And a partial decay scheme of ^(175)Er has been proposed for the first time.

关 键 词：丰中子核 稀土元素 内转换效应 衰变纲图 

分 类 号：O571.3[理学—粒子物理与原子核物理]