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arXiv · 1412.4574

Hidden dibaryons in one- and two-pion production in NN collisions

M. N. Platonova·V. I. Kukulin
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Abstract

Processes of one- and two-pion production in $NN$ collisions are considered in connection with excitation of intermediate dibaryon resonances. In particular, relative contributions of the conventional meson-exchange and dibaryon excitation mechanisms in the reaction $pp \to d π^+$ are investigated in detail. Inclusion of the intermediate isovector dibaryon resonances is shown to essentially improve the description of experimental data for this reaction, provided the soft meson-baryon form factors consistent with $πN$ elastic scattering are used. Manifestation of the intermediate isoscalar and isovector dibaryons in the two-pion production processes is also studied. The role of the isovector dibaryon resonances in the reaction $pp \to pp ππ$ is discussed for the first time. An explanation of the observed strong differences between two-pion production cross sections in $pn$ and $pp$ collisions based in part on the analysis of dibaryon structure is suggested.

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M. N. Platonova, V. I. Kukulin. 2016-01-13. Hidden dibaryons in one- and two-pion production in NN collisions. https://doi.org/10.1016/j.nuclphysa.2015.11.009

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