手征夸克模型下udss四夸克态的研究

在手征SU(3)夸克模型和扩展的手征SU(3)夸克模型的框架下, 用变分的方法系统地研究了同位旋为0、1, 自旋宇称为0⁺、1⁺和2⁺的udss四夸克系统6个低组态的能量. 模型的参数取自以前的工作, 它能很好地描述核子-核子散射相移以及核子-超子散射截面. S道相互作用的参数由拟合K介子和K^*介子的质量定出, 并且考虑了具有相同量子数的态之间的态混合效应. 结果表明, 同位旋为0且自旋宇称为1⁺的udss能量低于相应的K^*K^*,的阈能, 且该组态中KK^*的成分相当小, 因此该组态的宽度可能较小, 可视为一个可能的四夸克态的候选者.

Chiral Quark Model Study of ud(ss) Tetraquark States

The energies of the low-lying isoscalar and isovector ud(ss) configurations with spin-parity JP = 0+,1+, and 2+ are calculated in the chiral SU(3) quark model and the extended chiral SU(3) quark model by using the variational method. The model parameters are determined by the same method as in our previous work,and they still can satisfactorily describes the nucleon-nucleon scattering phase shifts and the hyperon-nucleon cross sections. The s-channel annihilation interaction is fixed by the masses of K and K* mesons, and the configuration mixing is considered. The results show that the ud(ss) configuration with I = 0 and JP = 1+ lies lower than the K*K* threshold, and furthermore, this state has a very small KK* component, thus it can be treated as a possible tetraquark candidate.