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Final-state $NN$-rescattering in spin asymmetries of $d(γ,π^-)pp$ reaction

Eed M. Darwish·Agus Salam
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Abstract

The role of the final-state $NN$-rescattering ($NN$-FSI) in the polarization observables of the inclusive reaction $d(γ,π^-)pp$, involving polarization of the photon beam and/or the deuteron target, is investigated. Various single- and double-spin asymmetries are studied with respect to the influence of such interaction effect and numerical predictions are given for forthcoming experiments. It has been found that the effect of $NN$-FSI is quite important for the single-spin asymmetries $Σ$, $T_{20}$, $T_{21}$ and $T_{22}$ and the double-spin asymmetry $T^{\ell}_{20}$, whereas it is much less important for the vector target asymmetry $T_{11}$ and other beam-target double-polarization asymmetries. Furthermore, we found that the inclusion of the $NN$-FSI improves the description of the LEGS data for the linear photon asymmetry.

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Eed M. Darwish, Agus Salam. 2005-04-30. Final-state $NN$-rescattering in spin asymmetries of $d(γ,π^-)pp$ reaction. https://doi.org/10.1016/j.nuclphysa.2005.04.026

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