非局部手征有效理论中的核子电磁形状因子
Nucleon electromagnetic form factors in nonlocal chiral effective theory
AI总结：
该研究在非局部手征有效理论框架下，通过纳入矢量介子耦合项并重新拟合低能耦合常数，显著改善了大$Q^2$区域核子电磁形状因子的$Q^2$依赖关系，使其与实验数据吻合。
AI中文摘要：
本文在非局部框架下计算了π介子单圈对核子电磁形状因子的修正，精度达到$\boldsymbol{\text{O}}(p^4)$阶。为系统研究矢量介子主导在模型中的作用，还包含了领头阶核子-矢量介子耦合项。由于手征低能耦合常数（LECs）依赖于重整化方案，我们将这些常数重新拟合到核子磁矩、电磁半径以及电磁形状因子的$Q^2$依赖关系。与之前的局部分析相比，模型结果显示，在非局部框架下，大$Q^2$区域内电磁形状因子的$Q^2$依赖关系得到显著改善，且与实验数据一致。
英文摘要：
In this paper, we calculate the pion one-loop corrections to the electromagnetic form factors of the nucleon up to $\mathcal{O}(p^4)$ order in the nonlocal framework. To systematically investigate the role of vector-meson dominance in the model, we also include the leading-order nucleon-vector-meson coupling. Owing to the renormalization-scheme dependence of chiral low-energy coupling constants (LECs), we refit these constants to the nucleon magnetic moments, electromagnetic radii, and the $Q^2$-dependence of the electromagnetic form factors. Compared with the previous local analysis, the model results show that, in the nonlocal framework, the $Q^2$-dependence of the electromagnetic form factors in the large-$Q^2$ region is significantly improved and are consistent with experimental data.
