Investigation on shape transitions and shape coexistences in neutron-rich odd-A and odd-odd nuclei around 100Zr

100Zr附近富中子奇A核和奇奇核的形状转变和形状共存研究

• 批准号: 452176002
• 负责人: Professor Dr. Jan Jolie
• 金额: --
• 依托单位: Department of Physics
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/452176002?language=en
• 关键词: Investigation; shape; transitions; coexistences; neutron

The proposal aims to provide new and improved spectroscopic information on odd-A and odd-odd nuclei in the vicinity of 100Zr mainly by lifetime measurements of low-energy excited states using fast-timing techniques. The goal is to obtain more spectroscopic evidences for the evolution of the neutron and proton single-particle orbitals in this particular mass region. The deduced gamma-ray transition rates will be compared with predictions using analytic collective models based on microscopically derived energy-density functionals which are able to describe the spherical-to-deformed shape transition and shape-coexistence phenomena observed in the vicinity of N = 60 isotones close to 100Zr. The candidates of interest to be measured are the even-odd 101Mo, the odd-even 103Tc and the odd-odd 102Tc nuclei. Other experimental data on the odd-even 99Y nucleus and the N = 59 odd-odd 98Y and 100Nb isotones have recently been acquired and requires to be analyzed. The neutron-rich candidates to be measured are well produced in thermal-neutron induced fission of, e.g. 235U. The experiments will be performed at the “Lohengrin” fission-fragment separator of the Institut Laue-Langevin (ILL) in Grenoble, France. In collaboration with the ILL and other international scientists, 3-4 fast-timing campaigns will be organized by the IKP. The IKP Köln high-performance LaBr3(Ce) detectors will be used for picosecond-sensitive lifetime determination with low-energy gamma rays via gamma-gamma or beta-gamma time-difference measurements. Installation, calibration and surveillance of the experiment will be done by the IKP fast-timing group. The experimental data will be analyzed on the high-speed IKP server using software specially compatible to the ILL data format and optimized for fast-timing analyzes. The new and improved lifetime results obtained will be used to calculate B(E2) and B(M1) transition rates for investigation on collectivity or for being used as input parameters to perform more phenomenological nuclear structure calculations. The new calculations within the framework of the Interacting-Boson-Fermion (-Fermion) model will be performed by theoretical nuclear structure physicists with whom we are successfully collaborating for many years. Our major objective is to obtain an improved insight on the evolution of shape transition and shape coexistence in nuclei close to 100Zr as a function of the proton and neutron number (orbitals) and to publish results and theoretical interpretations.

该提案旨在在100ZR附近提供有关ODD-A和ODD-ODD核的新的和改进的光谱信息，这主要是通过使用快速定时技术对低能量激发态的寿命测量。目的是获得更多的光谱证据，以在该特定质量区域中中子和质子单粒子轨道的演变。推导的伽马射线转变速率将与基于显微镜得出的能量密度函数的分析集体模型进行比较，该模型能够描述在接近100ZR接近100ZR的n = 60同位基因的附近观察到的球形对形状的形状转变和形状折叠现象。要测量的感兴趣的候选者是偶数101mo，奇数103tc和奇数102TC核里。最近获得了有关奇数99y核以及n = 59奇数98y和100nb同酮的其他实验数据，并需要进行分析。富含中子的候选物在热中子诱导的裂变中，例如235U。实验将在法国格林布勒市的Laue-Langevin研究所的“ Lohengrin”裂变分离器进行。与疾病和其他国际科学家合作，IKP将组织3-4个快速的运动。 IkpKöln高性能LABR3（CE）检测器将通过伽马 - 伽马或β-gamma时间差异测量测量，用于皮秒敏感的寿命测定。实验的安装，校准和监视将由IKP快速定时组完成。实验数据将在高速IKP服务器上使用特殊兼容ILL数据格式的软件进行分析，并进行了优化以进行快速计时分析。获得的新的和改进的寿命结果将用于计算集体投资的B（E2）和B（M1）过渡率，或用作输入参数，以执行更多现象学核结构计算。相互作用的 - 玻璃纤维（-fermion）模型的框架内的新计算将由理论核结构物理学家进行，我们与我们成功合作多年。我们的主要目标是获得对核和中子数（轨道）（轨道）的函数的核中形状转变和形状共存的进化的洞察力，并发表结果和理论解释。