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arXiv · 0709.0708

Pion Production in Neutrino-Nucleon Reactions

E. Hernandez·J. Nieves·M. Valverde
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Abstract

We construct a model for the weak pion production off the nucleon, which in addition to the weak excitation of the $Δ(1232)$ resonance and its subsequent decay into $Nπ$, it includes also some background terms required by chiral symmetry. We re-fit the $C_5^A(q^2)$ form factor to the flux averaged $ν_μp \to μ^-pπ^+$ ANL $q^2-$differential cross section data, finding a substantially smaller contribution of the $Δ$ pole mechanism than traditionally assumed in the literature. We also show that the interference between the Delta pole and the background terms produces parity-violating contributions to the pion angular differential cross section.

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BibTeXRIS

E. Hernandez, J. Nieves, M. Valverde. 2007-09-05. Pion Production in Neutrino-Nucleon Reactions. https://doi.org/10.1063/1.2834477

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