Title: Electromagnetism in Quark-Antiquark Bound States Show Chinese title

Title: 夸克-反夸克束缚态中的电磁学

Abstract: Non-perturbative proof is presented of a unique version of Goldstone theorem, that electromagnetism contributes to the masses of spinless particles of quark-antiquark bound states in the form of a commutator of the quark electric matrix and a coefficient factor which may be expressed simply in terms of a three-body Bethe-Salpeter amplitude, in the case where the Lagrangian conserves an approximate $SU(3)$ chiral symmetry. The coupled Bethe-Salpeter equation and Dyson-Schwinger equation in the ladder-rainbow approximation are layed out with every ingredient renormalized, which are applied to the problem of evaluating the mass differences of some charged and neutral pseudoscalar and vector mesons. The numerical results yield satisfactory agreement with experimental observations for the mass spectrum and meson decay constants. Estimates of the light quark masses are also given in the Bethe-Salpeter formalism. Show Chinese abstract

Abstract: 非微扰证明了Goldstone定理的一个独特版本，即在拉格朗日守恒近似的$SU(3)$手征对称性的情况下，电磁相互作用以夸克电荷矩阵与一个系数因子的对易子形式，对夸克-反夸克束缚态的无自旋粒子的质量作出贡献，该系数因子可以用三体Bethe-Salpeter振幅简单地表示。 在梯级-彩虹近似下，给出了重整化后的耦合Bethe-Salpeter方程和Dyson-Schwinger方程，并将其应用于计算某些带电和中性赝标量和矢量介子的质量差异问题。 数值结果对于质量谱和介子衰变常数与实验观测结果有令人满意的一致性。 此外，在Bethe-Salpeter框架下还给出了轻夸克质量的估计值。