The reaction γd→π+nn is calculated up to order χ5/2 in
chiral perturbation theory, where χ denotes the ratio of the pion to the
nucleon mass. Special emphasis is put on the role of nucleon--recoil
corrections that are the source of contributions with fractional power in
χ. Using the known near threshold production amplitude for γp→π+n as the only input, the total cross section for γd→π+nn
is described very well. A conservative estimate suggests that the theoretical
uncertainty for the transition operator amounts to 3 % for the computed
amplitude near threshold.Comment: 28 page