Fleming, M.*; Bernard, D.*; Brown, D.*; Chadwick, M. B.*; De Saint Jean, C.*; Dupont, E.*; Ge, Z.*; Harada, Hideo; Hawari, A.*; Herman, M.*; et al.
EPJ Web of Conferences, 239, p.15002_1 - 15002_4, 2020/09
Plompen, A. J. M.*; Cabellos, O.*; De Saint Jean, C.*; Fleming, M.*; Algora, A.*; Angelone, M.*; Archier, P.*; Bauge, E.*; Bersillon, O.*; Blokhin, A.*; et al.
European Physical Journal A, 56(7), p.181_1 - 181_108, 2020/07
The Joint Evaluated Fission and Fusion nuclear data library 3.3 is described. New evaluations for neutron-induced interactions with the major actinides U, U and Pu, on Am and Na, Ni, Cr, Cu, Zr, Cd, Hf, W, Au, Pb and Bi are presented. It includes new fission yileds, prompt fission neutron spectra and average number of neutrons per fission. In addition, new data for radioactive decay, thermal neutron scattering, gamma-ray emission, neutron activation, delayed neutrons and displacement damage are presented. JEFF-3.3 was complemented by files from the TENDL project. The libraries for photon, proton, deuteron, triton, helion and alpha-particle induced reactions are from TENDL-2017. The demands for uncertainty quantification in modeling led to many new covariance data. A comparison between results from model calculations using the JEFF-3.3 library and those from benchmark experiments for criticality, delayed neutron yields, shielding and decay heat, reveals that JEFF-3.3 is excellent for a wide range of nuclear technology applications, in particular nuclear energy.
Chadwick, M. B.*; Capote, R.*; Trkov, A.*; Herman, M. W.*; Brown, D. A.*; Hale, G. M.*; Kahler, A. C.*; Talou, P.*; Plompen, A. J.*; Schillebeeckx, P.*; et al.
Nuclear Data Sheets, 148, p.189 - 213, 2018/02
The CIELO collaboration has studied neutron cross sections on nuclides that significantly impact criticality in nuclear facilities - U, U, Pu, Fe, O and H - with the aim of improving the accuracy of the data and resolving previous discrepancies in our understanding. This multi-laboratory pilot project, coordinated via the OECD/NEA Working Party on Evaluation Cooperation (WPEC) Subgroup 40 with support also from the IAEA, has motivated experimental and theoretical work and led to suites of new evaluated libraries that accurately reflect measured data and also perform well in integral simulations of criticality. This report summarizes our results and outlines plans for the next phase of this collaboration.
Chadwick, M. B.*; Capote, R.*; Trkov, A.*; Kahler, A. C.*; Herman, M. W.*; Brown, D. A.*; Hale, G. M.*; Pigni, M.*; Dunn, M.*; Leal, L.*; et al.
EPJ Web of Conferences, 146, p.02001_1 - 02001_9, 2017/09
The CIELO collaboration has studied neutron cross sections on nuclides (O, Fe, U and Pu) that significantly impact criticality in nuclear technologies with the aim of improving the accuracy of the data and resolving previous discrepancies in our understanding. This multi-laboratory pilot project, coordinated via the OECD/NEA Working Party on Evaluation Cooperation (WPEC) Subgroup 40 with support also from the IAEA, has motivated experimental and theoretical work and led to suites of new evaluated libraries that accurately reflect measured data and also perform well in integral simulations of criticality.
Chadwick, M. B.*; Dupont, E.*; Bauge, E.*; Blokhin, A.*; Bouland, O.*; Brown, D. A.*; Capote, R.*; Carlson, A. D.*; Danon, Y.*; De Saint Jean, C.*; et al.
Nuclear Data Sheets, 118, p.1 - 25, 2014/04
CIELO (Collaborative International Evaluated Library Organization) provides a new working paradigm to facilitate evaluated nuclear reaction data advances. It brings together experts from across the international nuclear reaction data community to identify and document discrepancies among existing evaluated data libraries, measured data, and model calculation interpretations, and aims to make progress in reconciling these discrepancies to create more accurate ENDF-formatted files. The focus will initially be on a small number of the highest-priority isotopes, namely H, O, Fe, U, and Pu. This paper identifies discrepancies between various evaluations of the highest priority isotopes. The evaluated data for these materials in the existing nuclear data libraries are reviewed, and some integral properties are given. The paper summarizes a program of nuclear science and computational work needed to create the new CIELO nuclear data evaluations.
Batistoni, P.*; Angelone, M.*; Carconi, P.*; Fischer, U.*; Fleischer, K.*; Kondo, Keitaro; Klix, A.*; Kodeli, I.*; Leichtle, D.*; Petrizzi, L.*; et al.
Fusion Engineering and Design, 85(7-9), p.1675 - 1680, 2010/12
The EU is developing two test blanket modules (TBM), the Helium Cooled Pebble Bed (HCPB) and the Helium Cooled Lithium Lead (HCLL), which will be tested in ITER. Here neutronics experiments with a mockup for HCLL TBM were carried out. Detail distributions of the tritium production rate inside the mockup were measured with various methods. A lithium diamond detector developed as a neutron monitor for fusion devices has also been used as a tritium detector. Activation reaction rates inside the mockup were also measured. These measured data agreed with calculation results buy using MCNP and FENDL-2.1 within 10%, which demonstrated that the prediction accuracy was high. Sensitivity and uncertainty analyses suggested that the uncertainty of the tritium production rate from the nuclear data uncertainty was small, usually below 2%.
Kodeli, I.*; Trkov, A.*; Capote, R.*; Nagaya, Yasunobu; Maslov, V.*
Nuclear Instruments and Methods in Physics Research A, 610(2), p.540 - 552, 2009/11
The prompt fission neutron spectra covariance matrices of U, U and Pu were evaluated using the Monte Carlo method for two empirical spectra formulations, Watt and Kornilov, and compared to the existing evaluations such as JENDL-3.3. The fission spectra, together with the covariance matrices and the methods for the calculation of the corresponding sensitivity profiles were validated on several applications, including shielding (VENUS-3 benchmark, pressure vessel dosimetry) as well as on fast and thermal reactor systems (KRITZ and SNEAK critical experiments). A new set of parameters for a Kornilov model is proposed that improve both benchmark performance and the agreement with recently measured differential spectra. A recommendation to use constrained sensitivity coefficients was confirmed for the case of the fission spectrum induced uncertainty in the effective multiplication factor and in the detector responses, in order to assure the proper normalisation of the corresponding covariance matrices.
Nagaya, Yasunobu; Kodeli, I.*; Chiba, Go; Ishikawa, Makoto
Nuclear Instruments and Methods in Physics Research A, 603(3), p.485 - 490, 2009/03
This paper unveils that two types of sensitivity coefficients with respect to the fission spectrum exist: unconstrained and constrained sensitivity coefficients. The impact due to the difference of the coefficients has been investigated for the change in the effective multiplication factor and the uncertainty of the factor with respect to the fission spectrum. It is analytically shown that whichever of the sensitivity coefficients is used, the same result can be obtained. However, if the unconstrained sensitivity coefficient is used, the zero-sum constraint for the absolute covariance matrix must be satisfied with high accuracy in numerical applications.
Batistoni, P.*; Angelone, M.*; Bettinali, L.*; Carconi, P.*; Fischer, U.*; Kodeli, I.*; Leichtle, D.*; Ochiai, Kentaro; Perel, R.*; Pillon, M.*; et al.
Fusion Engineering and Design, 82(15-24), p.2095 - 2104, 2007/10
A neutronics experiment has been performed in the frame of European Fusion Technology Program on a mock-up of the EU Test Blanket Module (TBM), Helium Cooled Pebble Bed (HCPB) concept, with the objective to validate the capability of nuclear data to predict nuclear responses, such as the tritium production rate (TPR), with qualified uncertainties. In the experiment, the TPR has been measured using LiCO pellets at various depths at two symmetrical positions at each depth, one in the upper and one in the lower breeder cassette. Three independent measurements were performed by ENEA, TUD/VKTA and JAEA. The neutron flux in the beryllium layer was measured as well using activation foils.