A chiral effective Lagrangian for nuclei
A chiral effective Lagrangian for nuclei
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DOI：
10.1016/s0375-9474(96)00472-1
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发表时间：
1997-04-07
影响因子：
1.4
通讯作者：
Tang, HB
中科院分区：
文献类型：
--
作者：
Furnstahl, RJ;Serot, BD;Tang, HB
构造了一种与量子色动力学对称性一致且适用于有限密度系统的有效强子拉格朗日函数。自由度是（价）核子、π介子和低位非戈德斯通玻色子，它们解释了中程核子-核子相互作用，并方便地描述了核子双线性的非零期望值。手性对称性是非线性实现的，其中包含一个光标量介子作为手性单线态来描述中程核子-核子吸引力。核子的低能电磁结构在理论中使用矢量-介子优势来描述，因此不需要外部形状因素。有效拉格朗日在域及其导数的幂上得到扩展，并使用 Georgi 的“朴素维度分析”组织术语。使用模型中确定的单核子结构，给出了单重子环阶的有限核和核物质的结果。从核特性拟合获得的参数表明，朴素量纲分析是一个有用的原理，并且在场及其导数的前几个幂处截断有效拉格朗日是合理的。 (C) 1997 Elsevier Science B.V.
An effective hadronic lagrangian consistent with the symmetries of quantum chromodynamics and intended for applications to finite-density systems is constructed. The degrees of freedom are (valence) nucleons, pions and the low-lying non-Goldstone bosons, which account for the intermediate-range nucleon-nucleon interactions and conveniently describe the nonvanishing expectation values of nucleon bilinears. Chiral symmetry is realized nonlinearly, with a light scalar meson included as a chiral singlet to describe the mid-range nucleon-nucleon attraction, The low-energy electromagnetic structure of the nucleon is described within the theory using vector-meson dominance, so that external form factors are not needed. The effective lagrangian is expanded in powers of the fields and their derivatives, with the terms organized using Georgi's ''naive dimensional analysis''. Results are presented for finite nuclei and nuclear matter at one-baryon-loop order, using the single-nucleon structure determined within the model. Parameters obtained from fits to nuclear properties show that naive dimensional analysis is a useful principle and that a truncation of the effective lagrangian at the first few powers of the fields and their derivatives is justified. (C) 1997 Elsevier Science B.V.