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A model for pion Delta electroproduction on the proton

J. C. Nacher·E. Oset
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Abstract

We have extended a model for the $γN\to ππN$ reaction to virtual photons and selected the diagrams which have a $Δ$ in the final state. With this model we have evaluated cross sections for the virtual photon cross section as a function of $Q^2$ for different energies. The agreement found with the $γ_v p\toΔ^0π^+$ and $γ_v p\toΔ^{++}π^-$ reactions is good. The sensitivity of the results to $NΔ$ transition form factors is also studied. The present reaction, selecting a particular final state, is an extra test for models of the $γ_{v} N\to ππN$ amplitude. The experimental measurement of the different isospin channels for this reaction are encouraged as a means to unravel the dynamics of the two pions photoproduction processes.

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J. C. Nacher, E. Oset. 2000-03-02. A model for pion Delta electroproduction on the proton. https://doi.org/10.1016/s0375-9474(00)00165-2

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