Calculation of β-decay half-lives within a Skyrme-Hartree-Fock-Bogoliubov energy density functional with the proton-neutron quasiparticle random-phase approximation and isoscalar pairing strengths optimized by a Bayesian method
Calculation of β-decay half-lives within a Skyrme-Hartree-Fock-Bogoliubov energy density functional with the proton-neutron quasiparticle random-phase approximation and isoscalar pairing strengths optimized by a Bayesian method
复制标题
使用质子-中子准粒子随机相位近似和贝叶斯方法优化的等标量配对强度计算 Skyrme-Hartree-Fock-Bogoliubov 能量密度函数中的 β 衰变半衰期
DOI：
10.1103/physrevc.106.024306
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发表时间：
2022
影响因子：
3.1
通讯作者：
Haozhao Liang
中科院分区：
文献类型：
--
作者：
Futoshi Minato;Zhongming Niu;Haozhao Liang
背景：对于放射性核的数据，衰变提供了一些最重要的信息，适用于各个领域。然而，由于实验困难，一些衰变数据不可用。因此，在放射性核衰变的数据中嵌入了理论计算结果，以弥补缺失的信息。目的：为了进行理论衰变计算，必须尽可能精确地处理各种核关联。特别是，配对相关性是正确再现衰变半衰期的最重要因素之一。因此，我们首先研究了零和有限程等矢量配对对半衰期的影响。其次，我们调查的isoscope配对强度，这是通过实验数据的半衰期。最后，我们预测了丰中子核的等标对强度和半衰期。方法：为了计算衰变半衰期，在Skryne能量密度泛函之上应用质子-中子准粒子随机相近似，并假设球对称。通过包括允许和第一禁戒跃迁来计算半衰期。用贝叶斯神经网络（BNN）估计等密度配对强度。结果表明：有限程等矢量配对保证了衰变半衰期对模型空间的不敏感性，而零程等矢量配对则在很大程度上依赖于模型空间，用BNN等标量配对强度计算的衰变半衰期与实验数据吻合较好，但对高形变核的衰变半衰期被低估了。我们还研究了新的实验数据，没有用于BNN训练的预测性能，并发现他们是reproducedwell.Conclusions：我们的研究表明，由BNN确定的isoscope配对强度可以重现实验数据，具有相同的精度作为其他理论作品。为了实现更精确的预测，核形变是重要的。
Background:For data on radioactive nuclei,decay provides some of the most important information, applicable to various fields. However, some-decay data are not available due to experimental difficulties. For this reason, theoretically calculated results have been embedded in the data on radioactive nucleardecay to compensate for the missing information.Purpose:It is necessary to treat various nuclear correlations as precisely as possible for theoretical-decay calculations. In particular, the pairing correlation is one of the most important factors for reproducing-decay half-lives correctly. Therefore, we first study the effect of zero- and finite-range isovector pairings on half-lives. Second, we investigate the isoscalar pairing strengths, which are determined through experimental data of half-lives. Finally, we predict the isoscalar pairing strengths and half-lives of neutron-rich nuclei.Methods:To calculate the-decay half-lives, a proton-neutron quasiparticle random-phase approximation on top of a Skryme energy density functional is applied with an assumption of spherical symmetry. The half-lives are calculated by including the allowed and first-forbidden transitions. The isoscalar pairing strength is estimated by a Bayesian neural network (BNN). We verify the predicted isoscalar pairing strengths by preparing the training data and test data.Results:It was confirmed that the finite-range isovector pairing ensures that the-decay half-lives are insensitive to the model space, while the zero-range one is largely dependent on it. The half-lives calculated with the BNN isoscalar pairing strengths reproduced most of the experimental data, although those of highly deformed nuclei were underestimated. We also studied the predictive performance on new experimental data that were not used for the BNN training and found that they were reproduced well.Conclusions:Our study demonstrates that the isoscalar pairing strengths determined by the BNN can reproduce experimental data with the same accuracy as other theoretical works. To achieve a more precise prediction, the nuclear deformation is important.