论文标题
NAMBU JONA-LASINIO模型中轻标量介子的逆质量顺序
Inverse mass ordering of light scalar mesons in the Nambu Jona-Lasinio model
论文作者
论文摘要
通过将标量介子视为夸克和古quark的复合物体，在三种味道nambu jona-lasinio（NJL）模型中研究了低洼标量介子的质量。众所周知，一个简单的$ \ bar qq $图片无法重现标量介子的所谓逆质量订购。最近，通过引入由U（1）轴向异常引起的风味对称性破裂，在线性Sigma模型中提出了一种新的机制来再现标量介子观察到的质谱。在此提案的激励下，我们检查了这种新机制是否在NJL模型中起作用。通过计算标量介子质量，我们发现NJL模型以新术语的足够强度再现了观察到的质量排序。通过这种机制，事实证明，如果复制质量下有序，则组成奇怪的夸克质量将变成上下夸克的夸克。我们还讨论了标量diquark质量，以检查组成夸克质量与轻bary质量的堕落的一致性。
The masses of the low-lying scalar mesons are investigated in the three-flavor Nambu Jona-Lasinio (NJL) model by treating the scalar mesons as composite objects of a quark and an antiquark. It is known that a simple $\bar qq$ picture fails to reproduce so-called inverse mass ordering for the scalar mesons. Recently a new mechanism to reproduce the observed mass spectrum of the scalar mesons was proposed in a linear sigma model by introducing flavor symmetry breaking induced by the U(1) axial anomaly. Motivated by this proposal, we examine whether this new mechanism works also in the NJL model. By calculating the scalar meson masses, we find that the NJL model reproduces the observed mass ordering with sufficient strength of the new term. With this mechanism, it turns out that the constituent strange quark mass gets degenerate to that of the up and down quark if the inverse mass ordering is reproduced. We also discuss the scalar diquark masses to check the consistency of the degeneracy of the constituent quark masses with the light baryon masses.
