Abstract
An internal monostandard method for PGAA is proposed for completely non-destructive analysis of elements in bulky samples by the use of a neutron beam guided out from the reactor. The method is essentially the same as the k sub 0 method except that it corrects for the change of relative gamma -ray counting efficiencies caused by the absorption and scattering of neutrons and absorption of gamma -rays within the sample. Some examples of applications to archaeological samples of earthen wares, bronze mirrors, and to voluminous meteorite samples are demonstrated, and its future application to the in-situ studies of distribution and metabolism of a certain elements in animals is also explained.