Charge symmetry breaking effects in neutron-proton scattering using the quark model - art. no. 014307

Based on the formalism, using a pion exchange quark-quark force, developed by us earlier [Phys. Rev. C 53, 50 (1996)] to study the charge symmetry bre aking effects in nucleon-nucleon scattering we compute the difference in an alyzing power for polarized neutrons and polarized protons at 477 MeV labor atory energy. The formalism enables us to express the scattering amplitude in two parts: (i) a direct term due to pion exchange at the nucleon level a nd (ii) a quark exchange term involving the quark substructure of nucleons in terms of the momentum-dependent form factors appearing explicitly. The l atter has a structure that appears to be similar to the one obtained due to rho, omega exchanges between nucleons. Using these potentials we calculate the scattering amplitude for polarized neutron-proton scattering and compa re the results with the earlier works as well as with the experimental obse rvables.