论文标题
侏儒（偶极）共振的理论描述
Theoretical description of pygmy (dipole) resonances
论文作者
论文摘要
具有中子过量的稳定且不稳定的核显示 - 在等异位偶极转化强度分布中 - 中子发射阈值周围的小驼峰称为Pygmy偶极共振（PDR）。它的主要特征之一是等蛋白混合，允许与等异基探针进行实验研究。不同的理论方法和方法用于推断PDR的特征。在本章中，总结了这些低洼偶极状态的各种均值场理论及其扩展。特别关注的是对非弹性横截面的计算，这在使用等尺度探针（例如$α$ - 粒子或$^{17} $ o）的研究中尤其重要。径向形式因子的相关性与非弹性横截面计算有关。
Stable and unstable nuclei with neutron excess ($N>Z$) show - in the isovector dipole transition strength distribution - a small hump around the neutron emission threshold energy known as Pygmy Dipole Resonance (PDR). One of its main features is the isospin mixing allowing the experimental studies with both isovector and isoscalar probes. Different theoretical approaches and methodologies are used to deduce the characteristics of the PDR. In this Chapter, the various mean-field theories and their extensions, devoted to understand and reproduce the strength distribution of these low-lying dipole states, are summarised. Special attention is dedicated to the calculations of the inelastic cross section, aspect that is particularly important in the investigation with isoscalar probes, such as $α$-particles or $^{17}$O. The relevance of the radial form factors is presented in relation to the inelastic cross-section calculations.
