Structure of nuclei far from stability

在对其研究对象的基本理解方面，低能核物理学正处于一个重大范式转变的边缘。在轻核中，受量子色动力学（QCD）强相互作用理论的启发，现在有可能提供核结构的从头算预测，打破了几十年来由全局或局部拟合得出的现象有效相互作用的统治。这些方法用于分析光离子诱导反应，考虑到它们在统一框架内的结构；这违背了传统的核反应理论和核结构理论的分离。在加拿大粒子和核物理国家实验室（TRIUMF），加速器和复杂的伽玛射线探测系统的持续发展使人们能够研究远离稳定的原子核，从而测试人们对稳定和近稳定原子核的理解。一个显著的例子是由中子或质子过剩引起的核壳序的变化，它常常以意想不到的方式重新排列壳结构，并打破了可观测的趋势，如自旋/宇称、质量、结合能和接近稳定的激发能。受QCD启发，使用二体和三体相互作用的组态相互作用方法可以解决中等质量核的多体核问题，包括那些远离稳定的核，而密度泛函理论为研究这些相互作用的有效性提供了进一步的扩展，直到最重的核。目前的理论方法系统地跟踪由近似值施加的误差，预测趋势和不确定性。

Low-energy nuclear physics is on the verge of a significant paradigm shift in the basic understanding of its objects of study. In light nuclei it is now possible to provide ab-initio predictions of nuclear structure inspired by the Quantum Chromodynamics (QCD) theory of strong interactions, breaking a decades-long reign of phenomenological effective interactions derived from global or local fits to experimental data. These methods are used for analysis of light-ion induced reactions taking into account their structure within a unified framework; this defies the traditional separation between nuclear reaction and nuclear structure theories. At TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, sustained development in accelerators and sophisticated gamma-ray detection systems permits the study of nuclei very far from stability that tests understanding developed for stable and near-stable nuclei. A striking example is the change of nuclear shell ordering prompted by the neutron or proton excess that rearranges shell structure, often in unexpected ways, and breaks trends of observables such as spins/parities, masses, binding, and excitation energies established near stability. Configuration Interaction methods using two- and three-body interactions inspired by QCD allow the many-body nuclear problem to be solved for medium mass nuclei, including those far from stability, while density functional theories provide a further extension for investigating the validity of these interactions up to the heaviest nuclei. Current theoretical methods track errors imposed by approximations systematically, predicting trends together with uncertainties.