Collective correlations and excitation mechanism of nuclei near the drip-line : developments of cHFB linear response theory

滴线附近核的集体相关性和激发机制：cHFB线性响应理论的发展

基本信息

批准号：
14540250
负责人：
MATSUO Masayuki
金额：
$ 1.6万
依托单位：
Niigata University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

1.Quantitative aspects of the dineutron correlations in the medium mass near-drip-line O,Ca and Ni isotopes have been clarified by means of the coordinate space HFB theory. Two neutrons with spin singlet configuration are strongly correlated in the short distance region of 2-3fm, where the relative probability of the pair amounts up to 30-50%. The dineutron correlation is most enhanced in the external neutron skin region far outside the nuclear surface by 2-3fm. The correlation is found to exist also in the nuclear interior and in stable nuclei, indicating a generality of this correlation in nuclei.2.Microscopic structure of the dineutron correlation is investigated from the viewpoint of the configuration mixing and the Hartree-Fock single-particle orbits. It is clarified that the orbitals with high angular momenta and high quasiparticle energies contribute to formation of the correlation.3.The dineutron correlation in uniform nuclear matter in the superconducting phase has been investigated. It has been shown that the dineutron correlation is most significant at low densities with 1/5 to 1/100 of normal density. It is also shown that the dineutron correlation is quite general, being independent of the use of the zero or finite range forces.4.The dineutron character of the soft dipole excitation has been investigated in detail by means of the cHFB linear response theory (the continuum QRPA theory) in order to clarify the dominant particle-particle component : Analyzing the single-particle orbits contributing the soft dipole excitation, large contribution of high angular momentum orbittals is found, indicating that the di-neutron correlation plays a central role for this mode.5.We have completed a formulation of the continuum QRPA theory that incorporates the velocity dependent part of the Skyrme interaction for spin independent excitation modes.

1.利用坐标空间HFB理论阐明了中等质量近滴线O、Ca和Ni同位素中双中子相关性的定量问题。两个具有自旋单线态构型的中子在2-3fm的短距离区域中具有强相关性，其中该对的相对概率高达30-50%。双中子相关性在远离核表面2-3fm的外部中子表层区域增强最多。发现这种相关性在核内部和稳定的原子核中也存在，表明这种相关性在原子核中具有普遍性。 2.从构型混合和Hartree-Fock单粒子的角度研究了双中子相关性的微观结构轨道。阐明了高角动量和高准粒子能量的轨道有助于相关性的形成。3.研究了超导相均匀核物质中的双中子相关性。研究表明，双中子相关性在低密度（正常密度的 1/5 至 1/100）下最显着。还表明，双中子相关性非常普遍，与零范围力或有限范围力的使用无关。4.利用 cHFB 线性响应理论（连续统QRPA理论）为了澄清主要的粒子-粒子成分：分析对软偶极子激发有贡献的单粒子轨道，发现高角动量轨道的贡献很大，表明双中子相关性在该模式中起着核心作用。5.我们已经完成了连续介质 QRPA 理论的表述，该理论结合了自旋无关激发模式的 Skyrme 相互作用的速度相关部分。