标题： 味单态 g_A 来自格点 QCD 显示英文标题

标题： FLAVOR-SINGLET g_A FROM LATTICE QCD

摘要： 我们报告了从轴矢流得到质子的味单态轴耦合常数$g_A$的格点 QCD 计算。 模拟是在$\beta = 6$上在冻结的$16^3 \times 24$格点上进行的。 向手征极限的外推显示，相连插入项（价夸克和云部分）为$0.62 \pm 0.09$，这接近$g_A^8$。 真空极化（来自海夸克）对于$u$或$d$夸克是$- 0.12\pm 0.01 $，而$s$夸克也贡献了$-0.12\pm 0.01$。因此总$g_A^1$是$0.25 \pm 0.12$，这与实验结果一致。 此外，我们还发现 $g_A^3 = 1.20 \pm 0.11$, $g_A^8 = 0.61 \pm 0.13$ 和 $F_A/D_A = 0.60 \pm 0.02$，也与实验结果一致。 显示英文摘要

摘要： We report on a lattice QCD calculation of the flavor-singlet axial coupling constant $g_A$ of the proton from the axial-vector current. The simulation is carried out at $\beta = 6$ on a quenched $16^3 \times 24$ lattice. An extrapolation to the chiral limit shows that the connected insertion (valence and cloud parts) is $0.62 \pm 0.09$, which is close to $g_A^8$. The disconnected insertion (vacuum polarization from the sea quark) for the $u$ or $d$ quark is $- 0.12\pm 0.01 $ and the $s$ quark also contributes $-0.12\pm 0.01$. The total $g_A^1$ is thus $0.25 \pm 0.12$ which is in agreement with experiments. In addition, we find $g_A^3 = 1.20 \pm 0.11$, $g_A^8 = 0.61 \pm 0.13$ and $F_A/D_A = 0.60 \pm 0.02$, also in agreement with experiments.