Expanded COG criticality validation suite for inter-laboratory benchmark data comparison

Abstract

The COG suite of criticality benchmarks has been formally expanded from 591 to 3,395 to coverthe entire energy range from thermal to fast neutron spectra under a variety of reflector and moderator conditions and fissile materials. COG results have been compared with benchmark values from the International Criticality Safety Benchmark Evaluation Project Handbook for ENDF/B-VII.1, ENDF/BVIII.0 and JEFF-3.3. COG results have been also compared with a MERCURY validation suite. Most of the results agreed with the benchmark values within ±3σ. Among the three cross section data, cases with ENDF/B-VIII.0 performed best with about 85% of the total cases within ±3σ range. A major intercomparison project between COG, MCNP, MORET, and SCALE for ENDF/B-VIII.0 and JEFF-3.3 is in progress.