Lambda-Lambda potential from Lattice QCD simulations

利用格子上计算的Nambu-Bethe-Salpeter波函数求解耦合通道薛定谔方程，研究了具有奇异性的S=-2系统的重子-重子相互作用，特别是Lambda-Lambda相互作用。通过NBS波函数的构造，保证了用该方法提取的势矩阵能够再现适当的散射相移。利用这个势，计算了Lambda-Lambda和N-Xi散射相移。结果表明，在重夸克质量环境下可以发现H-双重子态，但随着轻夸克质量的减小，H-双重子态的能量趋于增大，导致了Lambda-Lambda能级与N-xi能级之间的共振态。

The baryon-baryon interactions with strangeness S=-2 system, especially for Lambda-Lambda interaction, had been investigated by solving the coupled channel Schroedinger equation using Nambu-Bethe-Salpeter wave functions which are evaluated on the lattice.The potential matrix extracted by this method is guaranteed to reproduce the proper scattering phase shift by construction through the NBS wave function. Using this potential, the Lambda-Lambda and N-Xi scattering phase shifts are calculated. The results show that H-dibaryon state can be found with heavy quark mass environment but its energy tends to be higher as decreasing light quark masses resulting in a resonance state between Lambda-Lambda and N-Xi energy levels.