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JAEA Reports

Development of the unified cross-section set ADJ2017R

Yokoyama, Kenji; Maruyama, Shuhei; Taninaka, Hiroshi; Oki, Shigeo

JAEA-Data/Code 2021-019, 115 Pages, 2022/03

JAEA-Data-Code-2021-019.pdf:6.21MB
JAEA-Data-Code-2021-019-appendix(CD-ROM).zip:435.94MB

In JAEA, several versions of unified cross-section set for fast reactors have been developed so far; we have developed a new unified cross-section set ADJ2017R, which is an improved version of the unified cross-section setADJ2017 for fast reactors. The unified cross-section set is used for reflecting information of C/E values (analysis / experiment values) obtained by integral experiment analyses in reactor core design via the cross-section adjustment methodology; the values are stored in the standard database for FBR core design. In the methodology, the cross-section set is adjusted by integrating the information such as uncertainty (covariance) of nuclear data, uncertainty of integral experiment / analysis, sensitivity of integral experiment with respect to nuclear data. ADJ2017R basically has the same performance as ADJ2017, but we conducted an additional investigation on ADJ2017 and revised the following two points. The first is to unify the evaluation method of the correlation coefficient of uncertainty caused by experiments (hereinafter referred to as the experimental correlation coefficient). Because it was found that the common uncertainty used in the evaluation of the experimental correlation coefficient was evaluated by two different methods, the experimental correlation coefficients were revised for all experimental data, and the evaluation method was unified. The second is the review of the integral experiment data used for the cross-section adjustment calculation. It was found that one of the experimental values of composition ratio after irradiation of the Am-243 sample has a problem in uncertainty evaluation because its experimental uncertainty is extremely small compared to the others. The cross-section adjustment calculation was, therefore, redone by excluding the experimental value. In the creation of ADJ2017, a total of 719 data sets were analyzed and evaluated, and eventually adopted 620 integral experimental data sets. In contrast, a total of 61

Journal Articles

Great achievements of M. Salvatores for nuclear data adjustment study with use of integral experiments

Yokoyama, Kenji; Ishikawa, Makoto*

Annals of Nuclear Energy, 154, p.108100_1 - 108100_11, 2021/05

 Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)

In the design of innovative nuclear reactors such as fast reactors, the improvement of the prediction accuracies for neutronics properties is an important task. The nuclear data adjustment is a promising methodology for this issue. The idea of the nuclear data adjustment was first proposed in 1964. Toward its practical application, however, a great deal of study has been conducted over a long time. While it took about 10 years to establish the theoretical formulation, the research and development for its practical application has been conducted for more than half a century. Researches in this field are still active, and the fact suggests that the improvement of the prediction accuracies is indispensable for the development of new types of nuclear reactors. Massimo Salvatores, who passed away in March 2020, was one of the first proposers to develop the nuclear data adjustment technique, as well as one of the great contributors to its practical application. Reviewing his long-time works in this area is almost the same as reviewing the history of the nuclear data adjustment methodology. The authors intend that this review would suggest what should be done in the future toward the next development in this area. The present review consists of two parts: a) the establishment of the nuclear data adjustment methodology and b) the achievements related to practical applications. Furthermore, the former is divided into two aspects: the study on the nuclear data adjustment theory and the numerical solution for sensitivity coefficient that is requisite for the nuclear data adjustment. The latter is separated to three categories: the use of integral experimental data, the uncertainty quantification and design target accuracy evaluation, and the promotion of nuclear data covariance development.

Journal Articles

The Joint evaluated fission and fusion nuclear data library, JEFF-3.3

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

 Times Cited Count:73 Percentile:99.41(Physics, Nuclear)

The Joint Evaluated Fission and Fusion nuclear data library 3.3 is described. New evaluations for neutron-induced interactions with the major actinides $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu, on $$^{241}$$Am and $$^{23}$$Na, $$^{59}$$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.

Journal Articles

Comparative study on prediction accuracy improvement methods with the use of integral experiments for neutronic characteristics of fast reactors

Yokoyama, Kenji; Kitada, Takanori*

Proceedings of 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) (CD-ROM), p.1221 - 1230, 2018/04

no abstracts in English

Journal Articles

Dimension-reduced cross-section adjustment method based on minimum variance unbiased estimation

Yokoyama, Kenji; Yamamoto, Akio*; Kitada, Takanori*

Journal of Nuclear Science and Technology, 55(3), p.319 - 334, 2018/03

 Times Cited Count:5 Percentile:64.98(Nuclear Science & Technology)

A new formulation of the cross-section adjustment methodology with the dimensionality reduction technique has been derived. This new formulation is proposed as the dimension reduced cross-section adjustment method (DRCA). Since the derivation of DRCA is based on the minimum variance unbiased estimation (MVUE), an assumption of normal distribution is not required. The result of DRCA depends on a user-defined matrix that determines the dimension reduced feature subspace. We have examine three variations of DRCA, namely DRCA1, DRCA2, and DRCA3. Mathematical investigation and numerical verification have revealed that DRCA2 is equivalent to the currently widely used cross-section adjustment method. Moreover, DRCA3 is found to be identical to the cross-section adjustment method based on MVUE, which has been proposed in the previous study.

Journal Articles

A New cross section adjustment method of removing systematic errors in fast reactors

Takeda, Toshikazu*; Yokoyama, Kenji; Sugino, Kazuteru

Annals of Nuclear Energy, 109, p.698 - 704, 2017/11

 Times Cited Count:2 Percentile:28.88(Nuclear Science & Technology)

A new cross section adjustment method has been derived in which systematic errors in measured data and calculated results of neutronics characteristics are estimated and removed in the adjustment. Bias factors which are the ratio between measured data and calculated results are used to estimate systematic errors. The difference of the bias factors from unity is caused generally by systematic errors and stochastic errors. Therefore by determining whether the difference is within the total stochastic errors of measurements and calculations, systematic errors are estimated. Since stochastic errors are determined for individual confidence levels, systematic errors are also dependent to the confidence levels. The method has been applied to cross section adjustments using 589 measured data obtained from fast critical assemblies and fast reactors. The adjustments results are compared with those of the conventional adjustment method. Also the effect of the confidence level to the adjusted cross sections is discussed.

Journal Articles

Methods and approaches to provide feedback from nuclear and covariance data adjustment for improvement of nuclear data files

Palmiotti, G.*; Salvatores, M.*; Yokoyama, Kenji; Ishikawa, Makoto

NEA/NSC/R(2016)6 (Internet), 42 Pages, 2017/05

Journal Articles

Development of a fast reactor for minor actinides transmutation; Improvement of prediction accuracy for MA-related integral parameters based on cross-section adjustment technique

Yokoyama, Kenji; Maruyama, Shuhei; Numata, Kazuyuki; Ishikawa, Makoto; Takeda, Toshikazu*

Proceedings of International Conference on the Physics of Reactors; Unifying Theory and Experiments in the 21st Century (PHYSOR 2016) (USB Flash Drive), p.1906 - 1915, 2016/05

Journal Articles

An Operator assistance system for beam adjustment of JAERI AVF cyclotron

Agematsu, Takashi; Arakawa, Kazuo; Okumura, Susumu; Nakamura, Yoshiteru; Tajima, Satoshi

KEK Proceedings 2003-19, p.27 - 29, 2004/03

Cyclotron start-up operations require dozens of adjustable parameters to be tuned to maximize extracted beam current. Experienced operators perform this process through trial and error using their experience and intuition. However, the process is difficult for inexperienced operators because operator need to adjust parameters using little information such as measured beam data, alarm, status of components, and so on. We have developed a computer-based visual assistance system for JAERI AVF cyclotron. The system provides a CRT display: the cyclotron beam trajectories, feasible setting regions, search traces and the beam envelopes for external beam transport designed to optimize beam parameter adjustment. The evaluation experiment for the system was carried out and the operation time to reach required beam conditions of the injection region of the cyclotron was reduced by approximately 65%. Also the system is very useful to study the problems on the beam transport such as beam trajectory, envelope, beam profile, spot size and so on.

Journal Articles

Adjustment of total delayed neutron yields of $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu by using results of in-pile measurements of effective delayed neutron fraction

Sakurai, Takeshi; Okajima, Shigeaki

Proceedings of International Conference on the New Frontiers of Nuclear Technology; Reactor Physics, Safety and High-Performance Computing (PHYSOR 2002) (CD-ROM), 12 Pages, 2002/10

The cross section adjustment method was applied to total delayed neutron yields of $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu of the JENDL-3.2 file by using experimental results of effective delayed neutron fraction $$beta_{eff}$$ at six cores built in two fast critical facilities of the MASURCA and FCA and a thermal critical facility of the TCA to improve these yields. The adjustment was carried out on the yields given at several incident neutron energy points in the file. Furthermore, to validate these adjusted delayed neutron yields, analyses were performed for the $$beta_{eff}$$ experiments at ZPR fast critical facility. These adjusted yields brought a reduction of uncertainty of calculated $$beta_{eff}$$ and an improvement in agreement of $$beta_{eff}$$ between experiment and calculation.

Journal Articles

Evaluation of Delayed Neutron Data for JENDL-3.3

Yoshida, Tadashi*; Okajima, Shigeaki; Sakurai, Takeshi; Nakajima, Ken; Yamane, Tsuyoshi; Katakura, Junichi; Tahara, Yoshihisa*; Zukeran, Atsushi*; Oyamatsu, Kazuhiro*; Osawa, Takaaki*; et al.

Journal of Nuclear Science and Technology, 39(Suppl.2), p.136 - 139, 2002/08

no abstracts in English

Journal Articles

Adjustment of total delayed neutron yields of $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu in JENDL-3.2 using benchmark experiments on effective delayed neutron fraction $$beta_{eff}$$

Sakurai, Takeshi; Okajima, Shigeaki

Journal of Nuclear Science and Technology, 39(1), p.19 - 30, 2002/01

 Times Cited Count:6 Percentile:41.16(Nuclear Science & Technology)

The cross section adjustment method was applied to total delayed neutron yields of $$^{235}$$U, $$^{238}$$U and $$^{239}$$Pu of the JENDL-3.2 file by using experimental results of effective delayed neutron fraction $$beta_{eff}$$ at six cores built in two fast critical facilities of the MASURCA and FCA and a thermal critical facility of the TCA to improve these yields. The adjustment was carried out on the yields given at several incident neutron energy points in the file. After the adjustment, the yield of $$^{238}$$U was almost uniformly decreased by about 3% below 7 MeV. The yield of $$^{239}$$Pu was increased by 2.6% and that of $$^{235}$$U was decreased by 0.9% at the thermal energy point, while the change of yield was less than 0.3% at the other energy points for these nuclides. By using these adjusted yields, the uncertainty of calculated $$beta_{eff}$$ was reduced and the agreement of $$beta_{eff}$$ between experiment and calculation was improved.

Journal Articles

Determination of neutron spectra formed by 40-MeV deuteron bombaredment on a lithium target with multi-foil activation technique

Maekawa, Fujio; Wada, Masayuki*; Von-Moellendorff, U.*; Wilson, P. P. H.*; Ikeda, Yujiro

Fusion Engineering and Design, 51-52(Part.B), p.815 - 820, 2000/11

 Times Cited Count:3 Percentile:27.47(Nuclear Science & Technology)

no abstracts in English

Journal Articles

Development of visual beam adjustment method for cyclotron

Agematsu, Takashi; Arakawa, Kazuo; Okumura, Susumu; Nakamura, Yoshiteru; Yokota, Wataru; Nara, Takayuki; Ishibori, Ikuo

JAERI-Review 95-019, p.211 - 213, 1995/10

no abstracts in English

Journal Articles

Optimization method of rod-type burnable poisons for nuclear designs of HTGRs

Yamashita, Kiyonobu

Journal of Nuclear Science and Technology, 31(9), p.979 - 985, 1994/09

 Times Cited Count:6 Percentile:53.35(Nuclear Science & Technology)

no abstracts in English

Journal Articles

Development of visual beam adjustment method for cyclotron

Agematsu, Takashi; Arakawa, Kazuo; Okumura, Susumu; Nakamura, Yoshiteru; Yokota, Wataru; Nara, Takayuki; Fukuda, Mitsuhiro; Ishibori, Ikuo; *; Tachikawa, T.*

Proc. of the 9th Symp. on Accelerator Science and Technology, p.65 - 67, 1993/00

no abstracts in English

Journal Articles

Actinide integral measurements in FCA assemblies

; ; ; ;

Nuclear Data for Basic and Applied Science,Vol.l, p.483 - 488, 1986/00

no abstracts in English

Journal Articles

Automatic query adjustment in document retrieval.

Dokumen Teshon Kenkyu, 28(5), p.175 - 187, 1978/05

no abstracts in English

Journal Articles

Adjustment to cross section data to fit integral experiments by least squares method

;

Journal of Nuclear Science and Technology, 12(11), p.663 - 680, 1975/11

 Times Cited Count:14

no abstracts in English

JAEA Reports

An Estimate of Uncertainties in the Experimental Data of $$^{2}$$$$^{3}$$$$^{5}$$U(n,f),$$^{2}$$$$^{3}$$$$^{9}$$Pu(n,f),$$^{2}$$$$^{3}$$$$^{8}$$U(n,$$gamma$$) Cross Sections

; Katsuragi, Satoru

JAERI-M 5536, 43 Pages, 1974/01

JAERI-M-5536.pdf:1.2MB

no abstracts in English

23 (Records 1-20 displayed on this page)