NN final-state interaction in two-nucleon knockout from 16 O
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.