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Theoretical study of the N N --> N N pi pi reaction

L. Alvarez-Ruso·E. Oset·E. Hernandez
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Abstract

We have developed a model for the N N --> N N pi pi reaction and evaluated cross sections for the different charged channels. The low energy part of those channels where the pions can be in an isospin zero state is dominated by N* excitation, driven by an isoscalar source recently found experimentally, followed by the decay N* --> N (pi pi, T=0, s-wave). At higher energies, and in channels where the pions are not in T=0, Delta excitation mechanisms become relevant. A rough agreement with the experimental data is obtained in most channels. Repercussions of the present findings for the ABC effect and the p p --> p p pi0 reaction close to threshold are also suggested.

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L. Alvarez-Ruso, E. Oset, E. Hernandez. 1998-01-26. Theoretical study of the N N --> N N pi pi reaction. https://doi.org/10.1016/s0375-9474(98)00126-2

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