近日，法国斯特拉斯堡大学的P.-A. Hervieux及其研究小组与法国巴黎萨克雷大学的X. Mougeot等人合作并取得一项新进展。经过不懈努力，他们揭示原子建模对电子捕获和振动过程的影响。相关研究成果已于2024年3月29日在国际知名学术期刊《物理评论A》上发表。

据悉，当前一项实验工作正以前所未有的精度测量电子捕获概率，这一研究对现有的理论模型提出了挑战。由于弱相互作用具有短程范围，因此要求对原子结构进行精确描述，直至原子核区域。为了深入探究衰变和振动概率受不同原子描述方式的影响，最近对电子捕获模型进行了优化。

为此，该研究团队在相对论密度泛函理论的框架下，精心开发了一个特定的原子模型，并深入探究了多种交换相关泛函和自相互作用校正模型。研究发现，光电离和电子捕获过程中的总振动概率测试结果，在很大程度上依赖于原子模型的精确度。为了验证模型的可靠性，团队将捕获概率的预测值与从⁷Be到¹³⁸La等不同放射性核素的现有公布实验数据进行了对比。值得欣慰的是，新的高精度测量数据为他们提供了宝贵的信息，因为目前实验值的精度尚不足以充分检验内壳以外的模型。

附：英文原文

Title: Influence of atomic modeling on electron capture and shaking processes

Author: A. Andoche, L. Mouawad, P.-A. Hervieux, X. Mougeot, J. Machado, J. P. Santos

Issue&Volume: 2024/03/29

Abstract: Ongoing experimental efforts to measure with unprecedented precision electron-capture probabilities challenge the current theoretical models. The short range of the weak interaction necessitates an accurate description of the atomic structure down to the nucleus region. A recent electron-capture modeling has been modified in order to test the influence of three different atomic descriptions on the decay and shaking probabilities. To this end, a specific atomic modeling was developed in the framework of the relativistic density-functional theory, exploring several exchange-correlation functionals and self-interaction-corrected models. It was found that the probabilities of total shaking, tested on both photoionization and electron-capture processes, depend strongly on the accuracy of the atomic modeling. Predictions of capture probabilities have been compared with experimental values evaluated from available published data for different radionuclides from ⁷Be to ¹³⁸La. New high-precision measurements are strongly encouraged because the accuracy of the current experimental values is insufficient to test the models beyond the inner shells.

DOI: 10.1103/PhysRevA.109.032826

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.032826