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Journal Articles

JENDL-4.0; A New library for innovative nuclear energy systems

Shibata, Keiichi; Iwamoto, Osamu; Nakagawa, Tsuneo; Iwamoto, Nobuyuki; Ichihara, Akira; Kunieda, Satoshi; Chiba, Satoshi; Katakura, Junichi; Otsuka, Naohiko*

Journal of the Korean Physical Society, 59(2), p.1046 - 1051, 2011/08

 Times Cited Count:18 Percentile:69.3(Physics, Multidisciplinary)

In JENDL-4, much emphasis is placed on the improvements of FP and MA data. For achieving this, new nuclear model codes POD and CCONE were developed, since experimental data are very scarce for those nuclei. The global coupled-channel optical model parameters, which were obtained in the wide mass region, were used for the evaluation of cross sections. Thermal cross sections of actinides were determined by carefully examining available experimental data. Special care was taken for the resonance region of $$^{235}$$U in order to reproduce measured criticalities and Na-void reactivities for U fueled fast-neutron cores. As for FP, resolved resonance parameters were updated for more than 100 nuclei. The cross sections of above the resonance region were evaluated by using the POD and CCONE codes. Fission product yield data were obtained from the ENDF/B-VII.0 data with some modifications. The new library, which contains neutron data for 406 nuclei, will be made available in 2010.

Journal Articles

Covariance evaluation for actinide nuclear data in JENDL-4

Iwamoto, Osamu; Nakagawa, Tsuneo; Chiba, Satoshi; Otsuka, Naohiko*

Journal of the Korean Physical Society, 59(2), p.1224 - 1229, 2011/08

 Times Cited Count:17 Percentile:68.09(Physics, Multidisciplinary)

Covariances of nuclear data in JENDL-4 have been evaluated. The covariance evaluations are basically based on available experimental data. The fission cross sections for 6 major actinides of $$^{233, 235, 238}$$U and $$^{239, 240, 241}$$Pu were evaluated simultaneously using experimental data of both cross sections and their ratios. The deduced covariance has correlations between the data of different nuclei. For minor actinide, covariances of the fission cross sections were obtained from evaluation using GMA code. For other many reaction cross sections, theoretical calculations with CCONE code were performed for cross section evaluations. The covariances were estimated using KALMAN code with sensitivities against model parameters. For resonance parameters and average number of fission neutrons, covariances were also evaluated.

Journal Articles

JENDL-4.0; A New library for nuclear science and engineering

Shibata, Keiichi; Iwamoto, Osamu; Nakagawa, Tsuneo*; Iwamoto, Nobuyuki; Ichihara, Akira; Kunieda, Satoshi; Chiba, Satoshi; Furutaka, Kazuyoshi; Otsuka, Naohiko*; Osawa, Takaaki*; et al.

Journal of Nuclear Science and Technology, 48(1), p.1 - 30, 2011/01

 Times Cited Count:1511 Percentile:100(Nuclear Science & Technology)

The fourth version of Japanese Evaluated Nuclear Data Library has been produced. In the new library, much emphasis is placed on the improvements of fission product and minor actinoid data. Two nuclear model codes were developed to evaluate the cross sections of fission products and minor actinoids. Coupled-channel optical model parameters, which can be applied to wide mass and energy regions, were obtained for nuclear model calculations. Thermal cross sections of actinoids were determined by considering recent experimental data or by the systematics of neighboring nuclei. A simultaneous evaluation was performed for the fission cross sections of important uranium and plutonium isotopes above 10 keV. The data on FP were re-evaluated, and new evaluations were performed for 30 nuclides. The data on light elements and structural materials were partly re-evaluated. The new library was released as JENDL-4.0 in May 2010.

Journal Articles

JENDL actinoid file 2008

Iwamoto, Osamu; Nakagawa, Tsuneo; Otsuka, Naohiko*; Chiba, Satoshi; Okumura, Keisuke; Chiba, Go; Osawa, Takaaki*; Furutaka, Kazuyoshi

Journal of Nuclear Science and Technology, 46(5), p.510 - 528, 2009/05

JENDL Actinoid File 2008 (JENDL/AC-2008) was released in March 2008. It includes nuclear data for neutron-induced reactions for 79 nuclides from Ac ($$Z=89$$) to Fm ($$Z=100$$). The neutron energy range is $$10^{-5}$$ eV to 20 MeV. Almost all data for 61 actinoids in JENDL-3.3 were revised. New evaluations were performed for 17 nuclides which have half lives longer than 1 day. New comprehensive theoretical model code CCONE was widely used for the evaluation of cross sections and neutron emission spectra. Thermal cross sections for many nuclides were revised based on experimental data. Resonance parameters were readjusted to reproduce them. Simultaneous evaluations of fission cross sections were performed for six important nuclei. The least-squares fitting code GMA was used for evaluation of fission cross sections for minor actinoid. In this paper, we present the evaluation methods and results of the JENDL/AC-2008.

Journal Articles

JENDL actinoid file 2008 and plan of covariance evaluation

Iwamoto, Osamu; Nakagawa, Tsuneo; Otsuka, Naohiko*; Chiba, Satoshi; Okumura, Keisuke; Chiba, Go

Nuclear Data Sheets, 109(12), p.2885 - 2889, 2008/12

 Times Cited Count:9 Percentile:53.24(Physics, Nuclear)

JENDL Actinoid File 2008 (JENDL/AC-2008) was released in March 2008. It provides nuclear data of neutron induced nuclear reactions for actinoid nuclides from Ac to Fm. The data for 62 nuclides in JENDL-3.3 were revised and newly evaluated data for 17 nuclides, which have a half-life longer than 1 day, were added. Nuclear reaction model code CCONE was widely used for the evaluations of cross sections and energy-angular distributions of secondary neutrons in fast energy region. Covariance data for the fission and capture cross sections and the number of neutrons per fission will be evaluated for important nuclides in the JENDL/AC-2008. The evaluation methods and the results will be presented and the plan of the covariance evaluations also will be mentioned.

Journal Articles

Toward the fourth version of Japanese Evaluated Nuclear Data Library (JENDL-4)

Shibata, Keiichi; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Otsuka, Naohiko*; Fukahori, Tokio; Nakagawa, Tsuneo; Katakura, Junichi

Proceedings of 16th Pacific Basin Nuclear Conference (PBNC-16) (CD-ROM), 6 Pages, 2008/10

Evaluated nuclear data play an important role in nuclear engineering. After we released the first version of Japanese Evaluated Nuclear Data Library JENDL-1 about 30 years ago, JENDL has been revised several times by considering the feedback from users and recent experimental data. JENDL-3.3, which was released in 2002, is being used in various fields, and its reliability has been confirmed. We are developing JENDL-4 for innovative reactors with much emphasis on the improvements of FP and MA data. Nuclear model codes were developed. The actinide data were already released as JENDL Actinoid File 2008. The complete library JENDL-4 will be made available in FY2009.

Journal Articles

Development of JENDL actinoid file

Iwamoto, Osamu; Nakagawa, Tsuneo; Otsuka, Naohiko*; Chiba, Satoshi; Okumura, Keisuke; Chiba, Go

Proceedings of International Conference on the Physics of Reactors, Nuclear Power; A Sustainable Resource (PHYSOR 2008) (CD-ROM), 8 Pages, 2008/09

Nuclear data for neutron induced reactions with actinides from Ac to Fm have been evaluated for JENDL Actinoid File (JENDL/AC). Almost all data in JENDL-3.3 have been updated based on available experimental data and using the newly developed theoretical model code CCONE. Integral benchmark tests for fission reactors are in progress using preliminary versions of JENDL/AC. The JENDL/AC will be released in 2008.

Journal Articles

Problem on unresolved resonance data in recent nuclear data libraries

Konno, Chikara; Nakagawa, Tsuneo; Ochiai, Kentaro; Sato, Satoshi; Yamauchi, Michinori

Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.1, p.713 - 716, 2008/05

A leakage neutron spectrum from a niobium sphere of 0.5 m in radius with a 20 MeV neutron in the center, which was calculated with ANISN, MCNP and JENDL-3.3, had a large strange bump around 100 keV, which originated from the unresolved resonance data. We checked cross section data of (n,$$gamma$$) reaction and elastic scattering in $$^{93}$$Nb with and without self-shielding correction by using a multigroup library of JENDL-3.3. The self-shielding correction of the unresolved resonances seems to be too large even around the upper energy of the unresolved resonance region. It is considered that the average reduced neutron widths or the upper energy of the unresolved resonance region in $$^{93}$$Nb have any problems. It is found out that many nuclei with unresolved resonance data in JENDL-3.3 and ENDF/B-VI have the similar problem. The unresolved resonance data in JENDL-3.3 and ENDF/B-VI should be revised by considering self-shielding correction in the next version.

Journal Articles

Recent advances in the JENDL project

Shibata, Keiichi; Nakagawa, Tsuneo; Fukahori, Tokio; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Otsuka, Naohiko; Katakura, Junichi; Watanabe, Yukinobu*; et al.

Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.2, p.727 - 732, 2008/05

General- and special-purpose JENDL data files are being produced in cooperation with the Japanese Nuclear Data Committee. We have developed nuclear model codes to improve the quality of MA and FP data. In the FP region, we obtained global coupled-channel optical model parameters, which can be applied to neutron- and proton-induced reaction data up to 200 MeV. These parameters are used for statistical model calculation. Resolved resonance parameters of MA and FP nuclei were updated to improve the low-energy behavior of the cross sections by using recent measurements. As a follow-up of JENDL-3.3, which was released in 2002, covarainces of several nuclei were estimated for a study on ADS. Concerning special-purpose files, the compilation of the 2007 versions of JENDL High Energy File and Photonulcear Data Files is in the final stage.

Journal Articles

Uranium-235 neutron capture cross section at keV energies

Otsuka, Naohiko; Nakagawa, Tsuneo; Shibata, Keiichi

Journal of Nuclear Science and Technology, 44(6), p.815 - 818, 2007/06

 Times Cited Count:4 Percentile:31.5(Nuclear Science & Technology)

The $$^{235}$$U neutron capture cross section was analyzedin the keV neutron energies by the least-squares method. The present analysis decreases the JENDL-3.3 cross sectionin the energy region from 20 to 200 keV and improves the C/E values of $$k_{rm eff}$$ for the BFS cores. The sodium void reactivity of the BFS cores is sensitiveto the capture cross sectionnear the upper limit of the resolved resonance region, where further investigation is necessary.

Journal Articles

Research activities of Japan Nuclear Data Committee in fiscal years of 2003 and 2004

Igashira, Masayuki*; Watanabe, Yukinobu*; Fukahori, Tokio; Okumura, Keisuke; Katakura, Junichi; Chiba, Satoshi; Shibata, Keiichi; Yamano, Naoki*; Nakagawa, Tsuneo; Odano, Naoteru*; et al.

Nihon Genshiryoku Gakkai Wabun Rombunshi, 6(1), p.85 - 96, 2007/03

This technical note summarizes research activities on nuclear data carried out by Japanese Nuclear Data Committee (JNDC) during the fiscal years of 2003 and 2004. During this period, the nuclear data files for special purposes (JENDL-HE-2004 and JENDL-PD-2004) were released. Other activities are described: analysis of post nuclear fuel irradiation experiments, nuclear chart and nuclear data evaluation for astrophysics.

Journal Articles

Uncertainty analyses of neutron cross sections for Nitrogen-15, Lead-206,207,208, Bismuth-209, Plutonium-238, Americium-242m, and Curium-244 in JENDL-3.3

Shibata, Keiichi; Nakagawa, Tsuneo

Journal of Nuclear Science and Technology, 44(1), p.1 - 9, 2007/01

 Times Cited Count:9 Percentile:54.96(Nuclear Science & Technology)

Covariances of neutron cross sections for $$^{15}N$$, $$^{206,207,208}Pb$$, $$^{209}Bi$$, $$^{238}Pu$$, $$^{242m}Am$$ and $$^{244}Cm$$ contained in JENDL-3.3 have been evaluated for the design of accelerator-driven transmutation systems. The covariances were obtained from the experimental data and model calculations on which the JENDL-3.3 data were based. The physical quantities for which covariances were deduced are the elastic scattering cross section of $$^{15}N$$, the inelastic scattering cross sections of $$^{206,207,208}Pb$$ and $$^{209}Bi$$, and the fission and capture cross sections of $$^{238}Pu$$, $$^{242m}Am$$ and $$^{244}Cm$$. Uncertainties in the resolved resonance parameters were estimated for $$^{238}Pu$$, $$^{242m}Am$$ and $$^{244}Cm$$. The results were compiled in the ENDF-6 format and merged with the JENDL-3.3 data.

Journal Articles

Status of the JENDL general-purpose file

Shibata, Keiichi; Nakagawa, Tsuneo; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Fukahori, Tokio; Otsuka, Naohiko; Katakura, Junichi

Proceedings of American Nuclear Society Topical Meeting on Physics of Reactors (PHYSOR 2006) (CD-ROM), 10 Pages, 2006/09

no abstracts in English

Journal Articles

Maxwellian-averaged neutron-induced reaction cross sections and astrophysical reaction rates for $$kT$$ = 1 keV to 1 MeV calculated from microscopic neutron cross section library JENDL-3.3

Nakagawa, Tsuneo; Chiba, Satoshi; Hayakawa, Takehito; Kajino, Toshitaka*

Atomic Data and Nuclear Data Tables, 91(2), p.77 - 186, 2005/11

 Times Cited Count:23 Percentile:79.78(Physics, Atomic, Molecular & Chemical)

no abstracts in English

Journal Articles

Estimation of covariance matrices for nuclear data of $$^{237}Np$$, $$^{241}Am$$ and $$^{243}Am$$

Nakagawa, Tsuneo

Journal of Nuclear Science and Technology, 42(11), p.984 - 993, 2005/11

 Times Cited Count:9 Percentile:53.26(Nuclear Science & Technology)

no abstracts in English

JAEA Reports

Program POD; A Computer code to calculate nuclear elastic scattering cross sections with the optical model and neutron inelastic scattering cross sections by the distorted-wave Born approximation

Ichihara, Akira; Kunieda, Satoshi; Chiba, Satoshi; Iwamoto, Osamu; Shibata, Keiichi; Nakagawa, Tsuneo; Fukahori, Tokio; Katakura, Junichi

JAERI-Data/Code 2005-004, 54 Pages, 2005/07

JAERI-Data-Code-2005-004.pdf:1.63MB

The computer code, POD, was developed to calculate angle-differential cross sections and analyzing powers for shape-elastic scattering for collisions of neutron or light ions with target nucleus. The cross sections are computed with the optical model. Angle-differential cross sections for neutron inelastic scattering can also be calculated with the distorted-wave Born approximation. The optical model potential parameters are the most essential inputs for those model computations. The cross sections and analyzing powers are obtained by using the existing local or global parameters. The parameters can also be inputted by users. In this report, the theoretical formulas, the computational methods, and the input parameters are explained. The sample inputs and outputs are also presented.

Journal Articles

New $$s$$-process path and its implications for a $$^{187}$$Re-$$^{187}$$Os nucleo-cosmochronometer

Hayakawa, Takehito; Shizuma, Toshiyuki; Kajino, Toshitaka*; Chiba, Satoshi; Shinohara, Nobuo; Nakagawa, Tsuneo; Arima, Taiko*

Astrophysical Journal, 628(1, Part1), p.533 - 540, 2005/07

 Times Cited Count:21 Percentile:51.61(Astronomy & Astrophysics)

no abstracts in English

Journal Articles

Status of the JENDL project

Shibata, Keiichi; Nakagawa, Tsuneo; Fukahori, Tokio; Ichihara, Akira; Iwamoto, Osamu; Otsuka, Naohiko*; Katakura, Junichi

AIP Conference Proceedings 769, p.171 - 176, 2005/05

The presentation deals with the activities on JENDL. JENDL-4 is being developed as a general purpose library. This library will include charged-particle and photon induced reaction data as well as spontaneous fission data for a limited number of nuclei in addition to neutron induced reaction data. The maximum incident energy can be extended to higher values than 20 MeV depending on data needs. Key subjects are improvements of accuracy of minor actinide and FP data, evaluations of covariances and so on. Quality assurance is regarded as important for JENDL-4. As special purpose files, we released the JENDL High Energy File and Photonuclear Data File this year. For the development of ADS, the Actinide File is being made. Furthermore,covariance data for some nuclei are also evaluated for ADS. Nuclear model codes are developed in order to reflect recent advances in nuclear theory on data evalulations. For users' covenience, we are working on the development of the Combined System for Nuclear Data Utilization, Circulaiton and Transfer.

Journal Articles

Web-based search and plot system for nuclear reaction data

Otsuka, Naohiko; Aikawa, Masayuki*; Suda, Takuma*; Naito, Kenichi*; Korennov, S.*; Arai, Koji*; Noto, Hiroshi*; Onishi, Akira*; Kato, Kiyoshi*; Nakagawa, Tsuneo; et al.

AIP Conference Proceedings 769, p.561 - 564, 2005/05

A web-based search and plot system for nuclear reaction data has been developed, covering experimental data in EXFOR format and evaluated data in ENDF format. The system is implemented for Linux OS, with Perl and MySQL used for CGI scripts and the database manager, respectively. Two prototypes for experimental and evaluated data are presented.

Journal Articles

Review of neutron cross-section evaluations for fission products

Oblozinsk$'y$, P.*; Herman, M.*; Mughabghab, S. F.*; Sirakov, I.*; Chang, J.*; Nakagawa, Tsuneo; Shibata, Keiichi; Kawai, Masayoshi*; Ignatyuk, A. V.*; Pronyaev, V. G.*; et al.

AIP Conference Proceedings 769, p.438 - 441, 2005/05

Review of neutron cross-section evaluations for fission products included in 5 major evaluated nuclear-data libralies was performed. The aim of the project, conducted under the WPEC Subgroup 21 during 2001-2004, was to prepare recommendations for best evaluations of nuclei in the range Z=1-68. Altogether, existing evaluations for 211 materials were reviewd, 7 new materials were added, and recommendations were prepared for 218 materials.

128 (Records 1-20 displayed on this page)