Generation of Consistent Data for Neutron Kinetics Models of the GRS System Code ATHLET

The paper describes the first experience at GRS with a switch algorithm built into the system code ATHLET, which allows to turn to point kinetics or 3D calculations with the neutronics core model QUABOX/CUBBOX and vica versa. The heart of the algorithm is the neutronics data generation code SIGMAS, developed and validated at GRS. Its basic characteristics and possibilities of applications are briefly described. As a demonstration of the algorithm, the results of two boron transient calculations performed with the switch coupling are presented and discussed.