稀土区奇A核晕带存在从转动到振动形状演化的直接证据（英文）  

Evidence for Rotational to Vibrational Evolution Along the Yrast Line in the Odd-A Rare-earth Nuclei

作　　者：周厚兵[1,2] 黄山 董国香 沈自序[1] 卢慧金 王乐乐 孙小军 许甫荣[4] ZHOU Houbing;HUANG Shan;DONG Guoxiang;SHEN Zixu;LU Huijin;WANG Lele;SUN Xiaojun;XU Furong(Department of Physics,Guangxi Normal University,Guilin 541004,Guangxi,China;Guangxi Key Laboratory Breeding Base of Nuclear Physics and Technology,Guangxi Normal University,Guilin 541004,Guangxi,China;School of Science,Huzhou University,Huzhou 313000,Zhejiang,China;School of Physics and SK Laboratory of Nuclear Physics Technology,Peking University,Beijing 100871,China)

机构地区：[1]广西师范大学物理科学与技术学院,广西桂林541004 [2]广西核物理与核技术重点实验室培育基地,广西桂林541004 [3]湖州师范学院,浙江湖州313000 [4]北京大学物理学院,北京100871

出　　处：《原子核物理评论》2018年第3期243-249,共7页Nuclear Physics Review

基　　金：National Natural Science Foundation of China(11505035,11465005,11505056,11605054,11675266,U1732138,11775057,11765004,11565008);Natural Science Foundation of Guangxi,China(2017GXNSFAA198160,2015GXNSFDA139004);Project of Innovative Team and Distinguished Scholar in Institutions of Higher Education of Guangxi,China~~

摘　　要：原子核的形状演化效应是核结构研究的重要基础问题之一。通常认为,A=160质量区的奇A核位于大形变核区域,它们的激发态能谱将呈现出典型的转动激发特征。然而,基于E-GOS曲线方法,发现随着角动量的增加,该质量区奇A核的晕带具有显著地从转动激发演化成为振动激发的形状演化现象。此外,为深入理解原子核形状演化的微观机制,采用Total-Routhian-Surface (TRS)方法针对稀土区的奇A核进行了理论计算,结果表明,^(165)Yb和^(157)Dy同位素在低激发态时具有稳定的长椭形变,当角动量大于0.50 MeV后,核芯的四极形变显著减小并开始产生三轴形变。The phase transition of nuclei with increasing angular momentum（or spin） and excitation energy is one of the most fundamental topics of nuclear structure research. The odd-N nuclei with A ≈160 are widely considered belonging to the well-deformed region, and their excitation spectra are energetically favored to exhibit the rotational characteristics. In this work, however, the evidence suggesting that the nuclei changes from rotation to vibration along the yrast lines as a function of spin was found. The simple method, named as E-Gamma Over Spin（E-GOS） curves, would be used to discern the evolution from rotational to vibrational structure in nuclei for various spin ranges. Meanwhile, in order to understand the band structure properties of nuclei, theoretical calculations have been performed for the yrast bands of the odd-A rare-earth nuclei within the framework of the total routhian surface（TRS） model. The TRS plots predict that the 165 Yb and157 Dy isotopes have large quadrupole shapes at low spin states. At higher rotational frequency（ ω〉 0.50 MeV）, a clear reduction of the quadrupole deformation is indicated by the present results, and the isotopes become rigid in the γ deformation.

关 键 词：相变 E-GOS曲线 总罗斯面 

分 类 号：O571.2[理学—粒子物理与原子核物理]