Spin-spin correlations in the reaction NN→NNπ at intermediate energies

Publisher Website
Google Scholar
Abstract
The authors predict the spin-spin correlations Ann, ASS, ALS, ASL and depolarisation parameter DNN for the reaction pp to np pi + in the geometry for exclusive, in-plane kinematics. Calculations are based on a relativistic and unitary three-body isobar model. The partial-wave isobar amplitudes TN alpha from NN (for alpha =P11 and P33 pi N quasiparticle interactions) are found by solving coupled Blankenbecler-Sugar integral equations with one-pion-exchange driver terms. Results are presented for several proton-pion angle pairs at Tlab=800 MeV and, for one angle pair, also at Tlab=500 and 1200 MeV. The correlations are typically large and change rapidly as kinematic conditions are varied. There is a moderate model-dependence in these predictions, as seen by comparing with calculations using heavy-boson-exchange modified partial-wave isobar amplitudes.