The n-p photodisintegration of heavy nuclei

Abstract The total cross section for direct absorption of γ-rays by neutron-proton pairs is evaluated for nuclear matter in the effective-mass approximation, and for photon energies up to about 200 MeV. Some consideration is given to the influence on the cross section of the finite size of actual nuclei. Electric dipole and quadrupole as well as magnetic dipole transitions are taken into account.