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The NN final-state interaction in the helicity structure of $\vec d(\vecγ,π^-)pp$ reaction

Eed M. Darwish
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Abstract

The influence of final-state $NN$-rescattering on the helicity structure of the $\vecγ\vec d\toπ^-pp$ reaction in the energy range from $π$-threshold up to 550 MeV has been investigated. The differential polarized cross-section difference for the parallel and antiparallel helicity states is predicted and compared with recent experimental data. It is shown that the effect of $NN$-rescattering is much less important in the polarized differential cross-section difference than in the previously studied unpolarized differential cross section. Furthermore, the contribution of $\vecγ\vec d\toπ^-pp$ to the spin asymmetry of the deuteron is explicitly evaluated over the region of the $Δ$(1232)-resonance with inclusion of $NN$-rescattering. The effect of $NN$ final-state interaction is found to be much larger in the asymmetry than in the total cross section and leads to an appreciable reduction of the spin asymmetry in the $Δ$-region.

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Eed M. Darwish. 2004-12-10. The NN final-state interaction in the helicity structure of $\vec d(\vecγ,π^-)pp$ reaction. https://doi.org/10.1016/j.nuclphysa.2004.12.039

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