Covariance Evaluation Methodology for Neutron Cross Sections
We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- Doe - Office Of Science
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 939948
- Report Number(s):
- BNL-81623-2008; R&D Project: 05055; KB0301041; TRN: US0806913
- Resource Relation:
- Conference: M3 Report prepared for GNEP, U.S. DOE Reactors Campaign; Brookhaven National Laboratory; 20080901 through 20080930
- Country of Publication:
- United States
- Language:
- English
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