By extending a coupled channels model which has proven successful in describing the reaction pp→${\pi }^{+}$d, we make predictions for charge symmetry breaking effects in the reaction np→d${\pi }^0$. We find that nucleon and delta mass differences at vertices where pions are emitted or absorbed are important (as for np elastic scattering). However, η-${\pi }^0$ mixing is also important in pion production. We predict forward-backward asymmetries in the pion production differential cross section as large as 1% (for laboratory energies below 800 MeV). The asymmetries induced in polarization observables are small.

• Received 22 June 1987

DOI:https://doi.org/10.1103/PhysRevC.38.838