论文标题
从晶状体QCD中的最大同胞蛋白散射两个和三个物理亲
Scattering of two and three physical pions at maximal isospin from lattice QCD
论文作者
论文摘要
我们提出了第一个直接$ n_f = 2 $ lattice QCD计算的两种和三$π^+$散射量，其中包括物理点的集合。我们研究了两杆相移的夸克质量依赖性以及三粒子相互作用参数。我们还将现象学和手性扰动理论（CHPT）进行比较。在两个粒子领域，我们在$ s $ - 和$ d $ - 波的现象学拟合中良好同意，并从直接计算的物理点获得$m_πa_0= -0.0481 $（86）$。在三粒子领域，我们观察到阈值达到领先的手性膨胀的合理一致，即。相比之下，我们观察到三粒子准局部散射量的能量依赖性部分无法通过领先顺序的chpt很好地描述。
We present the first direct $N_f=2$ lattice QCD computation of two- and three-$π^+$ scattering quantities that includes an ensemble at the physical point. We study the quark mass dependence of the two-pion phase shift, and the three-particle interaction parameters. We also compare to phenomenology and chiral perturbation theory (ChPT). In the two-particle sector, we observe good agreement to the phenomenological fits in $s$- and $d$-wave, and obtain $M_πa_0 = -0.0481(86)$ at the physical point from a direct computation. In the three-particle sector, we observe reasonable agreement at threshold to the leading order chiral expansion, i.e.\@ a mildly attractive three-particle contact term. In contrast, we observe that the energy-dependent part of the three-particle quasilocal scattering quantity is not well described by leading order ChPT.
