Coherent pion-photoproduction by deuterons at intermediate energies

Non-relativistically exact single scattering calculations for coherent pion photoproduction by deuterons at intermediate photon energies (200 MeV to 500 MeV) are presented. For the two-bodyγN→πN process we use the well-known dispersion theoretic model by Chewet al and for the deuteron wave-functions we employ the Yamaguchi and the two term Gaussian wave-function. We find that while both the wavefunctions reproduce the deuteron e.m. form factor reasonably well, the results for the pion photoproduction cross-section show, however, a sensitive dependence on their detailed forms. The angular distributions at various energies are found to have considerable variations from the usual impulse approximation calculations but tend to improve the agreement with the data in a large kinematical region.