Methods for shutdown worth calculations in fast reactors and their validation with help of SPX-1 absorber experiment evaluations

After the extensive evaluations of experiments performed in several zero power facilities, the SPX-1 startup experiments offered within the frame of the international collaboration the possibility for a validation of data and methods on a reactor core which is comparable in size with those reactors envisaged for the future. In this paper the methods used at Interatom and Kernforschungszentrum Karlsruhe (KfK) will be described and the present status of comparison of measured and calculated absorber worth values will be discussed. 8 refs, 5 figs