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Incoherent pion photoproduction on the deuteron with polarization observables II: Influence of final state rescattering

A. Fix·H. Arenhoevel
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Abstract

Incoherent pion photoproduction on the deuteron is studied for photon energies from threshold up to 1 GeV with special emphasis on polarization observables. The elementary $γN\toπN$ amplitude is taken from the MAID model. The influence of final state interactions on total and semi-exclusive cross sections $\vec d(\vecγ,π)NN$ is investigated by including complete rescattering in the final $NN$- and $πN$-subsystems. For charged pion-production the influence of $NN$-rescattering is moderate whereas $πN$-rescattering is almost negligible. Much stronger influences of $NN$-rescattering are seen in neutral pion production, which is due to the elimination of a significant spurious coherent contribution in the impulse approximation. Sizeable effects are also found in some of the beam, target and beam-target asymmetries of the differential cross section.

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A. Fix, H. Arenhoevel. 2005-06-06. Incoherent pion photoproduction on the deuteron with polarization observables II: Influence of final state rescattering. https://doi.org/10.1103/physrevc.72.064005

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