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

The role of the final-state NN-rescattering (NN-FSI) in the polarization observables of the inclusive reaction d (γ, π^-) p p, 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, T₂₀, T₂₁ and T₂₂ and the double-spin asymmetry T₂₀ ^ℓ, whereas it is much less important for the vector target asymmetry T₁₁ 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.