Electron capture on nuclei plays an essential role in the dynamics of several astrophysical objects, including core-collapse and thermonuclear supernovae, the crust of accreting neutron stars in binary systems and the final core evolution of intermediate-mass stars. In these astrophysical objects, the capture occurs at finite temperatures and densities, at which the electrons form a degenerate relativistic electron gas. The capture rates can be derived from perturbation theory, where allowed nuclear transitions [Gamow–Teller (GT) transitions] dominate, except at the higher temperatures achieved in core-collapse supernovae, where forbidden transitions also contribute significantly to the capture rates. There has been decisive progress in recent years in measuring GT strength distributions using novel experimental techniques based on charge-exchange reactions. These measurements not only provide data for the GT distributions of ground states for many relevant nuclei, but also serve as valuable constraints for nuclear models which are needed to derive the capture rates for the many nuclei for which no data yet exist. In particular, models are needed to evaluate stellar capture rates at finite temperatures, where capture can also occur on nuclei in thermally excited states. There has also been significant progress in recent years in the modeling of stellar capture rates. This has been made possible by advances in nuclear many-body models as well as in computer soft- and hardware. Specifically, to derive reliable capture rates for core-collapse supernovae, a dedicated strategy has been developed based on a hierarchy of nuclear models specifically adapted to the abundant nuclei and astrophysical conditions present under various collapse conditions. In particular, for the challenging conditions where the electron chemical potential and the nuclear Q values are of the same order, large-scale shell-model diagonalization calculations have proved to be an appropriate tool to derive stellar capture rates, often validated by experimental data. Such situations are relevant in the early stage of the core collapse of massive stars, for the nucleosynthesis of thermonuclear supernovae, and for the final evolution of the cores of intermediate-mass stars involving nuclei in the mass range A ∼ 20–65. This manuscript reviews the experimental and theoretical progress recently achieved in deriving stellar electron capture rates. It also discusses the impact these improved rates have on our understanding of the various astrophysical objects.

原子核上的电子俘获在几个天体物理物体的动力学中起着至关重要的作用，包括核心坍缩和热核超新星、双星系统中吸积中子星的外壳以及中等质量恒星的最终核心演化。在这些天体物理物体中，捕获发生在有限的温度和密度下，此时电子形成简并相对论电子气。捕获率可以从扰动理论推导出来，其中允许的核跃迁 [Gamow-Teller (GT) 跃迁] 占主导地位，除了在核心坍缩超新星中达到的更高温度下，禁止跃迁也对捕获率有显着贡献。近年来，在使用基于电荷交换反应的新型实验技术测量 GT 强度分布方面取得了决定性进展。这些测量不仅为许多相关核的基态 GT 分布提供数据，而且还作为核模型的宝贵约束，这些模型用于推导出许多尚不存在数据的核的捕获率。特别是需要模型来评估有限温度下的恒星捕获率，其中捕获也可能发生在处于热激发态的原子核上。近年来，在恒星捕获率建模方面也取得了重大进展。核多体模型以及计算机软件和硬件的进步使这成为可能。具体来说，为了获得核心坍缩超新星的可靠捕获率，基于核模型的层次结构开发了一种专门的策略，该模型专门适用于各种坍缩条件下存在的丰富的原子核和天体物理条件。特别是对于电子化学势和核Q值具有相同的数量级，大规模壳模型对角化计算已被证明是导出恒星捕获率的合适工具，通常由实验数据验证。这种情况与大质量恒星核心坍缩的早期阶段、热核超新星的核合成以及涉及质量范围A ∼ 20-65原子核的中等质量恒星核心的最终演化有关。这份手稿回顾了最近在推导恒星电子捕获率方面取得的实验和理论进展。它还讨论了这些提高的速率对我们对各种天体物理物体的理解的影响。