标题： 如何理解最轻的标量 显示英文标题

标题： How to understand the lightest scalars

摘要： 基于之前的论文，我讨论了我如何利用一个一般的耦合通道模型来理解最轻的标量粒子。 该模型包括所有轻的两介子阈值，Adler零点的约束，味对称的耦合，单位性和物理上可接受的解析性。 发现当耦合较大时，尽管只引入了一个裸的夸克-反夸克态，在第二叶上可能会出现两个物理共振极点。 因此，在这个模型中，f0(980)和f0(1370)共振极点是同一奇异-反奇异夸克态的两种表现形式。 另一方面，包含u和d夸克的同位旋标量态在单位化并受到强子质量位移强烈扭曲后，成为一个非常宽的共振态，其极点位于470-i250 MeV。 这是手征对称性自发破缺模型所需要的σ介子。 显示英文摘要

摘要： Based on previous papers I discuss how I understand the lightest scalars using a general coupled channel model. This model includes all light two-pseudoscalar thresholds, constraints from Adler zeroes, flavour symmetric couplings, unitarity and physically acceptable analyticity. One finds that with a large coupling there can appear two physical resonance poles on the second sheet although only one bare quark-antiquark state is put in. The f0(980) and f0(1370) resonance poles are thus in this model two manifestations of the same strange-antistrange quark state. On the other hand, the isoscalar state containing u and d quarks becomes (when unitarized and strongly distorted by hadronic mass shifts) a very broad resonance, with its pole at 470-i250 MeV. This is the sigma meson required by models for spontaneous breaking of chiral symmetry.