论文标题
以戈尔科夫·格林(Gorkov Green)的功能理论脱离单身魔术核
Moving away from singly-magic nuclei with Gorkov Green's function theory
论文作者
论文摘要
从钙到铬的钙周围,提出了七个完整的同位素链的批量计算(地面能量,均方根电荷半径和电荷密度分布)。计算是在Gorkov的Green的二阶工作方法中执行的,并利用两个最先进的两加二和三核子汉密尔顿人,$ nn $+$ 3N \ text {(lnl)} $和nnlo $ _ {\ text {sat}} $。与可用的实验数据达成了总体良好的一致性,尤其是当使用前(后者)相互作用时差异能量(电荷半径)。值得注意的是,中子魔法数量$ n = 28,32,34 $ $ n =随着实验趋势的出现和进化。相反,配对差距被系统地低估。电荷半径的同位素依赖性的一般特征也被复制,以及电荷密度分布。对于某些核,观察到理论描述的恶化,并归因于当前多体截断方案中(静态)四极相关的效率低下。为了解决这些局限性,我们主张形式主义的扩展以纳入旋转对称性的破坏,或者,或者,进行自我能源的随机抽样。
Ab initio calculations of bulk nuclear properties (ground-state energies, root mean square charge radii and charge density distributions) are presented for seven complete isotopic chains around calcium, from argon to chromium. Calculations are performed within the Gorkov self-consistent Green's function approach at second order and make use of two state-of-the-art two- plus three-nucleon Hamiltonians, $NN$+$3N\text{(lnl)}$ and NNLO$_{\text{sat}}$. An overall good agreement with available experimental data is found, in particular for differential energies (charge radii) when the former (latter) interaction is employed. Remarkably, neutron magic numbers $N=28,32,34$ emerge and evolve following experimental trends. In contrast, pairing gaps are systematically underestimated. General features of the isotopic dependence of charge radii are also reproduced, as well as charge density distributions. A deterioration of the theoretical description is observed for certain nuclei and ascribed to the inefficient account of (static) quadrupole correlation in the present many-body truncation scheme. In order to resolve these limitations, we advocate the extension of the formalism towards incorporating breaking of rotational symmetry or, alternatively, performing a stochastic sampling of the self-energy.