Physics calculations for charge design at Savannah River

The physics calculations used at Savannah River for charge design are described. A standard computational system, composed of modular computer codes and a data base, is used for routine design studies. Its primary functions consist of lattice and charge analysis. The system is supplemented by empirical procedures to improve its accuracy. Auxiliary computational techniques are employed, along with the standard system, for design of new assemblies and charge types. With these supplements, the standard system is sufficiently accurate and efficient to meet the current design needs of Savannah River