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arXiv · 1407.5445

Electroweak Form Factors of the $Δ$(1232) Resonance

Krzysztof M. Graczyk·Jakub Zmuda·Jan T. Sobczyk
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Abstract

Nucleon $\to Δ(1232)$ transition electroweak form factors are discussed in a single pion production model with nonresonant background terms originating from a chiral perturbation theory. Fits to electron-proton scattering $F_2$ as well as neutrino scattering bubble chamber experimental data are performed. Both $ν$-proton and $ν$-neutron channel data are discussed in a unified statistical model. A new parametrization of the $N\toΔ(1232)$ vector form factors is proposed. Fit to neutrino scattering data gives axial mass $M_{AΔ}=0.85{+0.09}{-0.08}\;$(GeV) and $C_5^A(0) = 1.10{+0.15}{-0.14}$ in accordance with Goldberger-Treiman relation as long as deuteron nuclear effects are considered.

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Krzysztof M. Graczyk, Jakub Zmuda, Jan T. Sobczyk. 2014-07-21. Electroweak Form Factors of the $Δ$(1232) Resonance. https://doi.org/10.1103/physrevd.90.093001

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