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Brookhaven Science Associates U.S. Department of Energy Covariance data: Status and Perspective at BNL D. Rochman, M. W. Herman, P. Obložinský National Nuclear Data Center, Brookhaven National Laboratory & T. Kawano T-16, Los Alamos National Laboratory
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Brookhaven Science Associates U.S. Department of Energy Methodology for covariance calculations at BNL Pointwise cross sections (with any energy groups) RRR (Resolved Resonance Region) URR (Unresolved Resonance Region) FaR (Fast Region) EMPIRE + KALMAN Resonance Module + KALMAN
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Brookhaven Science Associates U.S. Department of Energy General Procedure -Fast Region -Hauser Feshbach -Pre-equilibrium -… -Resonance Region -Breit Wigner -Reich Moore Models and parametersParametersSensitivity KALMAN Filter an optimal recursive data processing algorithm or Cross Section Uncertaintiesand CorrelationsParametersUncertainty RIPL & Parameter uncertainty adjustmentOptional: Thermal neutron capture Resonance Integral
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Brookhaven Science Associates U.S. Department of Energy General Procedure Up to today, this procedure was applied to: Gd-152 to Gd-160from 35 to 500 parameters (R 3 +URR+FaR) Am-241 790 parameters (R 3 +URR) Tc-99 1600 parameters (R 3 +URR) U-233, 234, 236from250 to3850 parameters (R 3 +URR) Resonance regionFast Region Breit Wigner, Reich Moore models Compound, pre-equilibrium, direct models E n, n, f 1 f2 Optical par., -strength func, level densities …
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Brookhaven Science Associates U.S. Department of Energy 152 Gd(n, ): Variance
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Brookhaven Science Associates U.S. Department of Energy 152 Gd(n, ): Correlation Energy-Energy Energy (MeV) 10 0.1 0.001 10 -5 10 -7
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Brookhaven Science Associates U.S. Department of Energy 155 Gd(n, ): Variance
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Brookhaven Science Associates U.S. Department of Energy 157 Gd(n, ): Correlation Energy-Energy Energy (MeV) 10 0.1 0.001 10 -5 10 -7
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Brookhaven Science Associates U.S. Department of Energy 241 Am(n,f): Variance
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Brookhaven Science Associates U.S. Department of Energy 241 Am(n,f), 234 U(n,f): Correlation Energy-Energy 234 U(n,f) Energy (MeV) 241 Am(n,f) 10 -7 10 -5 0.001 10 -7 10 -5 0.001
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Brookhaven Science Associates U.S. Department of Energy 236 U(n,f) and 99 Tc(n, ) Energy (MeV) 236 U(n,f) 99 Tc(n, ) Energy (MeV) 10 -7 10 -5 0.001 10 -7 10 -5 0.001
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Brookhaven Science Associates U.S. Department of Energy Production Schedule May 2006: proof of principle on 8 Gd isotopes, 241 Am, 99 Tc, 233 U, 234 U, 236 U End 2006: Codes ready and running on a 10-nodes cluster Mid 2007 : Production of covariances for selected materials End 2007: Low fidelity covariances for ENDF/A (if project approved) Covariance matrix available -in any multi-group representation -at any temperatures -in tabulated form or MF33 format
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