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NN final-state interaction in two-nucleon knockout from $^{16}O$

M. Schwamb·S. Boffi·C. Giusti·F. D. Pacati
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Abstract

The influence of the mutual interaction between the two outgoing nucleons (NN-FSI) in electro- and photoinduced two-nucleon knockout from $^{16}O$ has been investigated perturbatively. It turns out that the effect of NN-FSI depends on the kinematics and on the type of reaction considered. The effect is generally larger in pp- than in pn-knockout and in electron induced than in photoinduced reactions. In superparallel kinematics NN-FSI leads in the $(e,e'pp)$ channel to a strong increase of the cross section, that is mainly due to a strong enhancement of the $Δ$-current contribution. In pn-emission, however, this effect is partially cancelled by a destructive interference with the seagull current. For photoreactions NN-FSI is considerably reduced in superparallel kinematics and can be practically negligible in specific kinematics.

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M. Schwamb, S. Boffi, C. Giusti, F. D. Pacati. 2003-07-01. NN final-state interaction in two-nucleon knockout from $^{16}O$. https://doi.org/10.1140/epja%2Fi2003-10139-6

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