为了统一地采用谱函数的有限宽度描述,以同样的方式同时处理重子的基态与激发态,本文推广了Singh等提出的奇异重子的有限能量求和规则,得到能确定10个待求参数的完备方程组,即10个有限能量求和规则,并用数值方法得到奇异重子基态、第一和第二激发态的质量与衰变宽度.所得结果在求和规则误差范围内与实验值相符,并为统一处理强子基态与激发态的质量与宽度提供了一种新方法.
The framework of the theoretical treatment for finite energy sum rule is generalized to deal with both the ground state and the excited resonances of baryons in the same way, namely, all the spectrum functions of the ground and considered excited baryon states appearing in the dispersion relations are described by similar Breit-Wigner resonance form of finite width, and derivation of the masses and widths of the considered three low-lying resonances is also on the same footing. We expand Singh's method and work out the complete set of the equations for the finite-energy sum rules, including both expressions in the theoretical and the phenomenological sides. Based on these works, the numerical simulation methods are used to obtain the final results which are reasonably in agreement with the experimental data within the typical error of sum rule method.