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arXiv · 1501.03086

Electroweak Single Pion Production and Form Factors of the \Delta(1232) Resonance

Jakub Zmuda·Krzysztof M. Graczyk
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Abstract

We extend and review our analysis of the nucleon \to \Delta(1232) transition electroweak form factors from Ref. [1]. New fit of the \Delta(1232) vector form factors to electron-proton scattering F_2 structure function is introduced as well, leading to results different from the popular parametrization of Ref. [2]. A clear model dependence of the extracted parameters emerges. Fit to neutrino scattering data is performed in all available isospin channels. The resulting axial mass is M_{A\Delta}=0.85^{+0.09}_{-0.08} (GeV) and $C_5^A(0) = 1.10^{+0.15}_{-0.14}. The latter value is in accordance with Goldberger-Treiman relation as long as the deuteron effects are included.

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Jakub Zmuda, Krzysztof M. Graczyk. 2015-01-13. Electroweak Single Pion Production and Form Factors of the \Delta(1232) Resonance. https://doi.org/10.1063/1.4931872

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