Effects of the small components of the nucleon on pionic disintegration of deuterium near threshold

The nucleon pole diagram has been recalculated for pionic disintegration of deuterium, including the effects of the small components of the interacting nucleon by keeping all four invariants of the Blankenbecler and Cook vertex. The authors obtain the leading contribution to the cross section near threshold, in agreement with the Adler Dothan theorem. Following this result the S-wave rescattering mechanism generally required to explain the threshold region data is reexamined. (Auth.)