Monte Carlo Integration of the Adjoint Gamma-Ray Transport Equation

The adjoint transport problem for gamma radiation is formulated and prescriptions for its Monte Carlo solution are given. Emphasis is put upon requirements for calculation of effects in shielding against fallout and the differential effect of source position. Results are given for two situations: a detector three feet above a uniform infinite source of 1.25-MeV photons, and another detector placed in an open pit with a similar source.