P -wave nucleon-pion scattering amplitude in the Δ(1232) channel from lattice QCD
P -wave nucleon-pion scattering amplitude in the Δ(1232) channel from lattice QCD
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来自晶格 QCD 的 δ(1232) 通道中的 P 波核子 - π 介子散射幅度
DOI：
10.1103/physrevd.103.094508
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发表时间：
2021
影响因子：
5
通讯作者：
Rendon, Gumaro
中科院分区：
文献类型：
--
作者：
Silvi, Giorgio;Paul, Srijit;Alexandrou, Constantia;Krieg, Stefan;Leskovec, Luka;Meinel, Stefan;Negele, John;Petschlies, Marcus;Pochinsky, Andrew;Rendon, Gumaro
我们用晶格QCD和L方法确定了它们的共振参数。共振发生在同位旋波道内的弹性π-核子散射中。我们的计算是在晶格上的三叶草费米子的味道下进行的。介子质量和核子质量分别为和，强衰变通道位于阈值以上。为了彻底地描绘出核子-π子散射振幅的能量依赖关系，我们计算了所有相关的晶格对称群的不可约表示中的谱，直到总动量，包括混合和波的不对称。我们使用Breit-Wigner模型对波相移进行全局拟合，并对波相移进行有效范围扩展，将幅度参数全局拟合到高达21能级。从波散射振幅中极点的位置，我们得到了共振质量和耦合。
We determine theresonance parameters using lattice QCD and the Lüscher method. The resonance occurs in elastic pion-nucleon scattering within the isospin,-wave channel. Our calculation is performed withflavors of clover fermions on a lattice with. The pion and nucleon masses areand, respectively, and the strong decay channelis found to be above the threshold. To thoroughly map out the energy dependence of the nucleon-pion scattering amplitude, we compute the spectra in all relevant irreducible representations of the lattice symmetry groups for total momenta up to, including irreps that mixandwaves. We perform global fits of the amplitude parameters to up to 21 energy levels, using a Breit-Wigner model for the-wave phase shift and the effective-range expansion for the-wave phase shift. From the location of the pole in the-wave scattering amplitude, we obtain the resonance massand the coupling.