Low-Energy Limit of the Photodisintegration of the Deuteron

The exact transition amplitude for the photodisintegration of the deuteron at the zero-energy limit of the incident $\gamma$ ray is presented as a function of the electric charges and the magnetic moments of the proton, neutron, and deuteron, the effective range for triplet $n-p$ scattering, and the binding energy of the deuteron. The method used in this article is based on the theory of composite particles in quantum theory which has been developed by Nishijima, Zimmermann, and Haag. The low-energy limit presented here is the generalization of the Kroll-Ruderman theorem of pion photoproduction to the problem, including a composite particle.