This paper presents an update to the MK model [1], which was developed to describe single pion production in neutrino-nucleon interactions. Originally the MK model used the helicity amplitudes and the hadronic current form-factors of the Rein and Sehgal model [2]. The update includes a new definition for the helicity amplitudes in the first and second resonance regions, and new vector-current form factors. Fits to electron-proton scattering data were used to determine these vector-current form factors, and to assign errors to the constrained free parameters of the model.

中文翻译：

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电子-核子相互作用中的单π介子产生

本文介绍了对 MK 模型 [1] 的更新，该模型被开发用于描述中微子-核子相互作用中的单个 pion 产生。最初，MK 模型使用了 Rein 和 Sehgal 模型 [2] 的螺旋幅度和强子电流形状因子。更新包括对第一和第二共振区域中螺旋幅度的新定义，以及新的矢量电流形状因子。使用电子-质子散射数据拟合来确定这些矢量-电流形状因子，并将误差分配给模型的约束自由参数。