https://cea.hal.science/cea-02614125Nicol, T.T.NicolCEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) - CEA - Commissariat à l'énergie atomique et aux énergies alternativesCarmouze, C.C.CarmouzeCEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) - CEA - Commissariat à l'énergie atomique et aux énergies alternativesImpact of experimental correlation on transposition method carry out with critical integral experimentsHAL CCSD2019Statistical adjustmentExperimental correlationCRISTAL[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex][PHYS.NUCL] Physics [physics]/Nuclear Theory [nucl-th]CADARACHE, Bibliothèque2020-05-20 16:44:462022-06-26 00:31:142020-05-27 14:12:33enConference papersapplication/pdf1In order to estimate the bias on the effective multiplication factor (k$_{eff}$) of a criticalityapplication case, and the associated uncertainty due to Nuclear Data (ND), a method whichtakes advantage of the integral experiments information and is based on NDsensitivity/uncertainty analyses and adjustment, has been implemented in a tool called RIB(Représentativité, Incertitude, Biais). Such methodology has been worldwide studied for yearsin various fields. The RIB tool, developed at CEA, is related to the experimental validationdatabase of the French criticality-safety package, CRISTAL V2.0, containing more than 2000experiments from the International Criticality Safety Benchmark Evaluation Project handbook(ICSBEP) and French experimental programs. In most cases, even if a correlation is identifiedbetween the experiments, the value of this correlation might not be known.Validation tests of the RIB tool, in particular by arbitrary applying strong correlationsbetween integral experiments (>0.9), point out some unrealistic results: a strong deviation ofthe bias with significant reduction of the uncertainty due to ND. To check the RIB toolimplementation, transposition method equations have been implemented in Matlab. Anothertool developed at CEA and dedicated to ND evaluation, CONRAD (COde for NuclearReaction Analysis and Data Assimilation), has also been used to estimate bias and uncertaintydue to ND through the transposition method using integral experiments. Results obtained withthese three tools from several combinations « Application case/integral experiments », havebeen compared, confirming the RIB observed tendencies. Focusing on the post-adjustmentND, it seems that such phenomenon is associated to a strong variation of the cross sectionswhich may be due to Peelle’s pertinent puzzle effect. This paper describes the different toolsand presents the results obtained for the tested combinations « Application case/integralexperiments » in function of the experimental correlation factor. Some potential explanationsof the observed results, using strong experimental correlation factors, are discussed.