Detailed spectra data for the international handbook of evaluated critically safety benchmark experiments

Critical configurations described in the 'International Handbook of Evaluated Criticality Safety Benchmark Experiments' are being recalculated and detailed spectra data are being collected. These spectra data represent a significant enhancement to the handbook and will enable criticality safety practitioners to better understand the applicability of each configuration in the handbook. These data are published in a document that is separate from the handbook, but are linked to the appropriate evaluations in the handbook. Eventually, spectra data for every configuration that appears in the handbook will be available. These data were beginning to appear in the 1999 version of the Handbook. A description of the spectra data is included in this paper. (authors)