标题： SU(3)-味对称QCD中的弱束缚$H$双轻子 显示英文标题

标题： Weakly bound $H$ dibaryon from SU(3)-flavor-symmetric QCD

摘要： 我们展示了格点QCD连续极限中首次关于重子-重子相互作用的研究，发现存在出乎意料的大格点系统误差。 具体来说，我们在单一夸克质量点上确定了$H$二重子的结合能。 计算是在六个不同的晶格间距 $a$ 值下进行的，使用的是O($a$)改进的Wilson费米子，在SU(3)对称点处，具有 $m_\pi=m_K\approx 420$ MeV。 能量水平通过将变分方法应用于双局域双重子插值算符的相关矩阵来提取，这些算符是利用蒸馏技术计算得到的。 我们的分析采用Lüscher的有限体积量子化条件，从能谱确定散射相移，并反之亦然，既适用于两重子阈值以下也适用于以上的情况。 我们对格点谱进行全局拟合，拟合参数化相移，并辅以描述离散化效应的项，然后将格点间距外推到零。 发现相移和由此确定的结合能受到格点系统误差的强烈影响。 我们在三味QCD连续极限中的结合能估计值为 $B_H^{\text{SU(3)}_{\rm f}}=4.56\pm1.13_{\rm stat}\pm0.63_{\rm syst}$ MeV。 显示英文摘要

摘要： We present the first study of baryon-baryon interactions in the continuum limit of lattice QCD, finding unexpectedly large lattice artifacts. Specifically, we determine the binding energy of the $H$ dibaryon at a single quark-mass point. The calculation is performed at six values of the lattice spacing $a$, using O($a$)-improved Wilson fermions at the SU(3)-symmetric point with $m_\pi=m_K\approx 420$ MeV. Energy levels are extracted by applying a variational method to correlation matrices of bilocal two-baryon interpolating operators computed using the distillation technique. Our analysis employs L\"uscher's finite-volume quantization condition to determine the scattering phase shifts from the spectrum and vice versa, both above and below the two-baryon threshold. We perform global fits to the lattice spectra using parametrizations of the phase shift, supplemented by terms describing discretization effects, then extrapolate the lattice spacing to zero. The phase shift and the binding energy determined from it are found to be strongly affected by lattice artifacts. Our estimate of the binding energy in the continuum limit of three-flavor QCD is $B_H^{\text{SU(3)}_{\rm f}}=4.56\pm1.13_{\rm stat}\pm0.63_{\rm syst}$ MeV.