Neutron-proton charge-exchange polarization

The neutron-proton charge-exchange polarization has provided new information to test various theoretical models and exchange degeneracy of ρ and A2 trajectories. The small polarization which is consistently negative and independent of energy at most points is changing our belief that particles like ρ and A2 are exchange degenerate. We are considering here a theoretical model which is capable of reproducing the desired np-pn polarization that has been found experimentally. This model for which the polarization has given reasonable qualitative and quantitative agreement with experimental data is consistent when we study simultaneously the polarizations and differential cross-sections for the processes np → pn and pp- → nn-.