Borosilicate glass (α,n) sources used with ORIGEN-type calculations

The major part of the neutron sources in vitrified high level waste is produced from the actinide α-particle emission interacting with the light elements in borosilicate glass. Models applying thick target (α,n) yield data have been developed for the ALPHN code and ORIGEN-S at the Oak Ridge national Laboratory. The method requires the relation between the (α,n) yields and the stopping powers of elements, which are constituents in a mixture, and the total (α,n) yield of the mixture. An example is shown of results computed by ALPHN, listing the calculated (α,n) sources for each α-particle emitter in addition to the total. In this paper an example computed by ORIGEN-S is given, showing both the total (α,n) spectrum and the total neutron spectrum, including spontaneous fission. A discussion of the limited validation work is also provided