arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2008.09745nucl-thnucl-ex
收藏

核能级密度集体增强的微观模型

Microscopic model for the collective enhancement of nuclear level densities

Jie Zhao, Tamara Nikšić, Dario Vretenar

摘要:

在能量密度泛函框架下,发展了一种计算核能级密度的微观方法。本征能级密度计算从单准粒子光谱中得到的有限温度自洽平均场(SCMF)计算,考虑到核变形,并指定的能量密度功能(EDF)和配对相互作用的选择。总能级密度是通过将本征密度与相应的集体能级密度进行卷积来计算的,集体能级密度由五维四极或四极加八极集体哈密顿量的本征态确定。的哈密顿量(惯性参数,集体势)的参数一致地确定由变形约束SCMF计算使用相同的EDF和配对相互作用。应用该模型计算了$^{94,96,98}$ Mo、$^{106,108}$ Pd、$^{106,112}$ Cd、$^{160,162,164}$ Dy、$^{166}$ Er和$^{170,172}$ Yb的NLD,并与已有数据进行了比较。结果表明,集体增强的本征能级密度,一贯计算相应的集体哈密顿量的本征态,导致总NLD是在整个能量范围内的测量值的数据非常吻合。

英文摘要:

A microscopic method for calculating nuclear level densities (NLD) is developed, based on the framework of energy density functionals. Intrinsic level densities are computed from single-quasiparticle spectra obtained in a finite-temperature self-consistent mean-field (SCMF) calculation that takes into account nuclear deformation, and is specified by the choice of the energy density functional (EDF) and pairing interaction. The total level density is calculated by convoluting the intrinsic density with the corresponding collective level density, determined by the eigenstates of a five-dimensional quadrupole or quadrupole plus octupole collective Hamiltonian. The parameters of the Hamiltonian (inertia parameters, collective potential) are consistently determined by deformation-constrained SCMF calculations using the same EDF and pairing interaction. The model is applied in the calculation of NLD of $^{94,96,98}$Mo, $^{106,108}$Pd, $^{106,112}$Cd, $^{160,162,164}$Dy, $^{166}$Er, and $^{170,172}$Yb, in comparison with available data. It is shown that the collective enhancement of the intrinsic level density, consistently computed from the eigenstates of the corresponding collective Hamiltonian, leads to total NLDs that are in excellent agreement with data over the whole energy range of measured values.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑