标题： ε-区域中静态近似下介子关联函数的低能模贡献 显示英文标题

标题： Low-lying mode contribution to the quenched meson correlators in the epsilon-regime

摘要： 我们展示了用重叠费米子在极小质量下（2.6至13 MeV）的介子相关函数的淬火计算。在这个区域，派生子康普顿波长大于我们的晶格尺寸L\simeq 1.23 fm，系统处于有效场论中的epsilon区域。我们发现，在这个范围内，标量和伪标量相关函数被少数低能费米子本征模式精确地近似，而轴向矢量相关函数则受到较高本征模式的重要贡献。我们还测量了不相连的伪标量相关函数，它被低能模式很好地饱和。通过将这些晶格数据与淬火手征微扰理论中相关函数的一阶表达式相匹配，我们评估了衰变常数F_pi和手征凝聚Sigma以及参数m_0和alpha，它们描述了淬火近似产生的效应。 显示英文摘要

摘要： We present a quenched calculation of meson correlators with the overlap fermion at very small masses 2.6--13 MeV. In this region the pion Compton wavelength is larger than our lattice size L\simeq 1.23fm and the system is in the so-called epsilon-regime of chiral perturbation theory. We found that the scalar and pseudo-scalar correlators are precisely approximated by a few hundred low-lying fermion eigenmodes in this regime, whereas axial-vector correlator receives significant contributions from higher eigenmodes. We also measure the disconnected pseudo-scalar correlator, which is well saturated with the low-lying modes. Matching these lattice data with the one-loop expressions for the correlators in quenched chiral perturbation theory, we evaluate the decay constant F_pi and the chiral condensate Sigma as well as the parameters m_0 and alpha, which describe the artifacts of the quenched approximation.