Checking, processing and verification of nuclear data covariances

Abstract

The aim of this paper is to present the activities carried out by NEA Data Bank on checking, processing and verification of JEFF-3.3T4 covariances. A picture of the completeness and status of the JEFF-3.3T4 covariances is addressed. The verification of JEFF-3.3T4 covariances is performed with nuclear data sensitivity tool providing the keff uncertainty as a function of the contributing nuclide-reaction pairings including cross-reaction covariances. A total number of 4501 ICSBEP benchmarks is used in this analysis. This exercise is also extended to covariance libraries such as JENDL-4.0 updated files, ENDF/B-VII.1, SCALE-6.2rev8 and ENDF/B-VIII.0β5, allowing comparison of these results with both the experimental criticality benchmark and different methodologies of evaluation.