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arXiv · 1305.5076

Pion photoproduction on nucleus with two-nucleon emission

I. V. Glavanakov·A. N. Tabachenko
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Abstract

A model for the pion photoproduction on nuclei in the $A\left({γ,\, πNN} \right)B$ reaction is presented. This is an extension of our recent model for the $A\left({γ,\, πN} \right)B$ reaction. In this approach we have moved beyond the standard shell-model considering $Δ$\textit{N} correlations in the nuclear wave functions, which are caused by the virtual transitions $NN \to ΔN \to NN$ in the ground state of the nucleus. The main ingredients of the model are the two- and three-particle density matrices and the transition operators $γΔ\to Nπ$ and $γN \to Nπ$. The direct and exchange reaction mechanisms, which follow from the structure of the density matrices, are examined. The model is used to investigate the $^{12}$C$\left({γ,\, π^{+} p} \right)$ and $^{12}$C$\left({γ,\, π^{-} p} \right)$ reactions in the kinematic region of the large momentum transfers to the residual nuclear system, where the pion production occurs with the emission of two nucleons.

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I. V. Glavanakov, A. N. Tabachenko. 2013-05-22. Pion photoproduction on nucleus with two-nucleon emission. https://doi.org/10.1016/j.nuclphysa.2013.07.009

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