标题： 手征平均场模型在核物理中的分析 显示英文标题

标题： Analysis of Chiral Mean-Field Models for Nuclei

摘要： 基于包含狄拉克核子和经典标量与矢量介子场的相对论能量泛函的核性质分析被讨论。 密度泛函理论表明，该能量泛函可以包含超出简单哈特里近似的多体效应。 利用有效场论的基本思想，发展了一种能量泛函的系统截断方案，该方案基于介子场及其梯度的幂级数展开。 通过考虑实现量子色动力学中自发破缺的手征对称性的特定拉格朗日量，并在哈特里水平上研究它们，分析了手征模型。 包含一个轻标量介子作为π介子的手征伙伴和中程核子-核子相互作用媒介的模型，以及包含“墨西哥帽”势的模型，无法再现核的基本基态特性。 相反，具有对称性非线性实现的手征模型被证明包含了通用能量泛函中固有的全部灵活性，因此可以成功描述核。 显示英文摘要

摘要： An analysis of nuclear properties based on a relativistic energy functional containing Dirac nucleons and classical scalar and vector meson fields is discussed. Density functional theory implies that this energy functional can include many-body effects that go beyond the simple Hartree approximation. Using basic ideas from effective field theory, a systematic truncation scheme is developed for the energy functional, which is based on an expansion in powers of the meson fields and their gradients. Chiral models are analyzed by considering specific lagrangians that realize the spontaneously broken chiral symmetry of QCD in different ways and by studying them at the Hartree level. Models that include a light scalar meson playing a dual role as the chiral partner of the pion and the mediator of the intermediate-range nucleon-nucleon interaction, and which include a "Mexican-hat" potential, fail to reproduce basic ground-state properties of nuclei. In contrast, chiral models with a nonlinear realization of the symmetry are shown to contain the full flexibility inherent in the general energy functional and can therefore successfully describe nuclei.