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Journal Articles

ACE library of JENDL-4.0/HE

Matsuda, Norihiro; Kunieda, Satoshi; Okamoto, Tsutomu*; Tada, Kenichi; Konno, Chikara

Progress in Nuclear Science and Technology (Internet), 6, p.225 - 229, 2019/01

Journal Articles

Overview of JENDL-4.0/HE and benchmark calculations

Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.

JAEA-Conf 2016-004, p.41 - 46, 2016/09

Neutron- and proton-induced cross-section data are required in a wide energy range beyond 20 MeV, for the design of accelerator applications. New evaluations are performed with recent knowledge in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p+$$^{6,7}$$Li and p+$$^{9}$$Be which have been highly requested from a medical field. The present high-energy nuclear data library, JENDL-4.0/HE, includes evaluated cross-sections for incident neutrons and protons up to 200 MeV (for about 130 nuclei). We overview substantial features of the library, i.e., (1) systematic evaluation with CCONE code, (2) challenges for evaluations of light nuclei and (3) inheritance of JENDL-4.0 and JENDL/HE-2007. In this talk, we also focus on the results of benchmark calculation for neutronics to show performance of the present library.

JAEA Reports

Improvement of WWW chart of the nuclides interface

Okamoto, Tsutomu; Minato, Futoshi; Koura, Hiroyuki; Iwamoto, Osamu

JAEA-Data/Code 2015-029, 30 Pages, 2016/03

JAEA-Data-Code-2015-029.pdf:1.81MB

The booklet "chart of the nuclides" is issued every 4 years since 1976 from Nuclear Data Center, JAEA. The chart of the nuclides for WWW (World Wide Web) was developed in 1999 in order to be available from internet browser. Internet connection speeds, browser functions and JavaScript libraries has, however, progressed at present compared with the internet technology in those days. In connection with the release of the 2014 edition of the chart of the nuclides, the interface of the WWW chart of the nuclides has been improved by introducing new internet technologies aiming at enhancing convenience on accessibilities via browsers. We introduced a scrolling screen that would make capabilities of easy screen movement on a map with the addition of the drag scrolling function. Considering smart phone access, the light-weight edition which introduced automatic switch was prepared. The new system results in reduction in access time and usefulness in mobile environment. The method of making figures of the chart was reconsidered due to addition of new decay schemes to the 2014 edition. SVG (Scalable Vector Graphics) was adopted so as to make figures easily. It is concluded that the accessibilities of WWW chart of the nuclides are substantially improved from the previous version by introducing the new technologies.

Journal Articles

Sensitivity analyses of initial compositions and cross sections for activation products of in-core structure materials

Yamamoto, Kento; Okumura, Keisuke; Kojima, Kensuke; Okamoto, Tsutomu

Nuclear Back-end and Transmutation Technology for Waste Disposal, p.233 - 249, 2015/00

To improve the prediction accuracy of concentrations of activation products (APs) in the field of nuclear back-end, it is important to investigate the elements and the nuclear reactions leading to generation of APs. To clarify quantitatively the source elements and the nuclear reactions dominating generation of APs, sensitivity analyses of initial compositions and cross sections were conducted using ORIGEN2.2 code and ORLIBJ40, which is a set of the 1-group cross section libraries based on JENDL-4.0. Activations of cladding tubes, end-plugs and spacers of fuel assemblies and channel boxes in BWR, whose materials are zirconium alloy, stainless steel, and nickel-chromium-based alloy, were analyzed. The results clarified quantitatively the source elements and the nuclear reactions dominating generation of APs. It was remarkable that the dominant generation pathways were clarified even for the nuclides generated through complicated pathways. In conclusion, the results of sensitivity analyses could be utilized to select the objective of elements for measurements of impurities in the materials and of nuclear data for improvement of accuracy.

JAEA Reports

Main generation pathways of activation products for in-core structure materials (Joint research)

Yamamoto, Kento; Okumura, Keisuke; Kojima, Kensuke; Okamoto, Tsutomu

JAEA-Research 2013-038, 88 Pages, 2014/02

JAEA-Research-2013-038.pdf:3.15MB

Accurate information on main generation pathways of activation products is important to improve the accuracy of predicting the concentrations of activation products. Using ORIGEN2 and ORLIBJ40, which is a set of the cross section libraries based on JENDL-4.0, the initial compositions and the cross sections which influence on the concentrations of activation products were clarified by executing the sensitivity analyses on them. Activations of cladding tubes, end-plugs and spacers of fuel assemblies and channel boxes, which were composed of Zircaloy, SUS304, and Inconel-718, were analyzed. The main generation pathways of some significant activation products were summarized from the results of sensitivity analyses.

Journal Articles

Nuclear data for severe accident analysis and decommissioning of nuclear power plant

Okumura, Keisuke; Kojima, Kensuke; Okamoto, Tsutomu; Hagura, Hiroyuki; Suyama, Kenya

JAEA-Conf 2013-002, p.15 - 20, 2013/10

Three-dimensional nuclide inventory and decay heat analysis were performed for the Fukushima Dai-ichi Power Plants (1F1, 1F2, 1F3) by using MOSRA system with JENDL-4.0 library. In the analysis, nuclide inventory for approximately 1400 nuclides were estimated in consideration of radial and axial burn-up and void distributions. Total decay heat and its distribution in each plant were estimated by the sum of all nuclide contributions. The obtained decay heat was compared with the results of simple evaluation formulas used in severe accident analyses. The results of the simple evaluation formulas agree with our results within 20%. For future decommissioning of commercial nuclear power plants, new activation cross-sections library for ORIGEN-S is also under development in the cooperative study program between JAEA and JAPCO. The present status and future plan are shown from view points of nuclear data and method.

JAEA Reports

A Set of ORIGEN2 cross section libraries based on JENDL-4.0; ORLIBJ40

Okumura, Keisuke; Sugino, Kazuteru; Kojima, Kensuke; Jin, Tomoyuki*; Okamoto, Tsutomu; Katakura, Junichi*

JAEA-Data/Code 2012-032, 148 Pages, 2013/03

JAEA-Data-Code-2012-032.pdf:6.99MB

A set of cross section libraries for the isotope generation and depletion calculation code ORIGEN2 was produced by using recent nuclear data JENDL-4.0. In this new library (ORLIBJ40), neutron-induced cross sections, fission product yields, isomeric ratios and half-lives were updated. ORLIBJ40 includes 24 libraries for typical UO$$_{2}$$ or MOX fuels of PWR and BWR. In addition, it includes 36 libraries for various fast reactor fuels. ORLIBJ40 was applied to the post irradiation examination analyses of LWR nuclear spent fuels. As a result, it was confirmed that improvements were achieved especially for inventory and radioactivity estimations of minor actinides (Am and Cm isotopes) and fission products sensitive to cross sections (Eu and Sm isotopes) and for long-lived fission products ($$^{79}$$Se, etc.), compared with other existing ORIGEN2 libraries.

Journal Articles

Production of the ORIGEN2 library based on JENDL-4.0 for high temperature engineering test reactor

Kojima, Kensuke; Okumura, Keisuke; Okamoto, Tsutomu; Goto, Minoru

Proceedings of 6th International Topical Meeting on High Temperature Reactor Technology (HTR 2012) (USB Flash Drive), 7 Pages, 2012/10

A set of the ORIGEN2 library for High Temperature engineering Test Reactor (HTTR) was newly produced in order to improve prediction accuracy of burn-up characteristics such as spent fuel composition, radioactivity and decay heat. In the library, cross sections and decay data are adopted from JENDL-4.0 and from ENSDF. In the production of effective cross sections and neutron spectrum, MVP-BURN based on the continuous-energy Monte Carlo method and a statistical geometry model is applied to the HTTR fuel with many coated fuel particles. In this way, the double heterogeneous effect of the HTTR fuel can be accurately taken into account. By using the neutron spectrum obtained in the MVP-BURN calculation, infinite dilution cross sections from JENDL-4.0 are condensed to one-group cross sections. The burn-up calculation results of ORIGEN2 with the produced library and those of MVP-BURN with detail modeling and much calculation cost show good agreement for burn-up changes of fuel composition.

Journal Articles

Development of the ORIGEN2 library for light water reactors based on JENDL-4.0

Okumura, Keisuke; Kojima, Kensuke; Okamoto, Tsutomu

JAEA-Conf 2012-001, p.89 - 94, 2012/07

New ORIGEN2 libraries (ORLIBJ40) for light water reactors were developed based on JENDL-4.0. It was validated by post irradiation examination analyses of nuclear spent fuels. As a result, it was found that drastic improvements were achieved especially for the inventory estimations of minor actinides (Np, Am and Cm isotopes) and fission products sensitive to cross sections (Eu and Sm isotopes) compared with old ORIGEN2 libraries. Furthermore, radioactivity of long-lived fission products, such as $$^{79}$$Se and $$^{135}$$Cs were also improved because of implementations of new half-life data. These nuclides are very important for long-term safety assessment of a geological disposal of the vitrified wastes.

JAEA Reports

Nuclide inventories of spent fuels from light water reactors

Okumura, Keisuke; Okamoto, Tsutomu

JAEA-Data/Code 2011-020, 193 Pages, 2012/02

JAEA-Data-Code-2011-020.pdf:33.53MB

Accurate information on nuclide inventories of spent fuels from Light Water Reactors (LWRs) is important for evaluations of criticality, decay heat, radioactivity, toxicity, and so on, in the safety assessments of storage, transportation, reprocessing and waste disposal of the spent fuels. So, a lot of lattice burn-up calculations were carried out for the possible fuel specifications and irradiation conditions in Japanese commercial LWRs by using the latest nuclear data library JENDL-4.0 and a sophisticated lattice burn-up calculation code MOSRA-SRAC. As a result, burn-up changes of nuclide inventories and their possible ranges were clarified for 21 heavy nuclides and 118 fission products, which are important from the viewpoint of impacts to nuclear characteristics and nuclear fuel cycle and environment.

Journal Articles

New ORIGEN2 libraries based on JENDL-4.0 and their validation for long-lived fission products by post irradiation examination analyses of LWR spent fuels

Kojima, Kensuke; Okumura, Keisuke; Asai, Shiho; Hanzawa, Yukiko; Okamoto, Tsutomu; Toshimitsu, Masaaki; Inagawa, Jun; Kimura, Takaumi; Kaneko, Satoru*; Suzuki, Kensuke*

Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 5 Pages, 2011/12

Accurate inventory estimation of long-lived fission products (LLFPs) in LWR spent fuels is important for the quality management and for long-term safety assessment of high-level radioactive vitrified wastes. In Japan, ORIGEN2 has been widely used to estimate the fuel compositions. However, equipped library data in the original ORIGEN2 are old and are not validated enough for LLFPs, such as $$^{79}$$Se, $$^{99}$$Tc, $$^{126}$$Sn and $$^{135}$$Cs, because available post irradiation examination (PIE) data are limited for these nuclides, which have difficulties in radiochemical analyses. For more accurate the estimation, new ORIGEN2 libraries are developed from the latest nuclear data library JENDL-4.0 for cross sections and fission yields, and from other libraries for half-lives, and so on. The new libraries are validated by PIE analyses of the sample fuels irradiated in Cooper, Calvert-Cliffs-1, H. B. Robinson-2, and Ohi-1. As a result, it was found that the new library gives good results for the estimation.

Journal Articles

Analyses of assay data of LWR spent nuclear fuels with a continuous-energy Monte Carlo code MVP and JENDL-4.0 for inventory estimation of $$^{79}$$Se, $$^{99}$$Tc, $$^{126}$$Sn and $$^{135}$$Cs

Okumura, Keisuke; Asai, Shiho; Hanzawa, Yukiko; Suzuki, Hideya; Toshimitsu, Masaaki; Inagawa, Jun; Okamoto, Tsutomu; Shinohara, Nobuo; Kaneko, Satoru*; Suzuki, Kensuke*

Progress in Nuclear Science and Technology (Internet), 2, p.369 - 374, 2011/10

For accurate inventory estimation of long-lived fission products in LWR spent fuels, a new burn-up chain model and decay data based on the latest nuclear data such as JENDL-4.0 was developed. MVP-BURN with the latest nuclear data was applied to several post irradiation examinations including inventory measurements of $$^{79}$$Se, $$^{99}$$Tc, $$^{126}$$Sn and $$^{135}$$Cs. One of them is a new measurement by JAEA. From the PIE analyses, it is found that the new PIE data obtained by JAEA is consistent with the other PIE data by different laboratory with different techniques. It is also confirmed that the present calculation results show good agreements with experimental ones within about 10% for productions of $$^{79}$$Se and $$^{135}$$Cs. In contrast, amounts of $$^{99}$$Tc and $$^{126}$$Sn are overestimated by about 50%. These discrepancies are likely due to the effect of insoluble residue produced during sample dissolution and/or errors of fission yields in the analyses.

Journal Articles

Computational study for inventory estimation of Se-79, Tc-99, Sn-126, and Cs-135 in high-level radioactive wastes from spent nuclear fuels of light water reactors

Okumura, Keisuke; Asai, Shiho; Hanzawa, Yukiko; Okamoto, Tsutomu; Suzuki, Hideya; Toshimitsu, Masaaki; Inagawa, Jun; Kimura, Takaumi; Suzuki, Kensuke*; Kaneko, Satoru*

Proceedings of 14th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM 2011) (CD-ROM), p.1443 - 1450, 2011/09

Inventory estimation of long-lived fission products (LLFPs) in high-level radioactive wastes (HLW) from spent nuclear fuels of light water reactors is important for a safety assessment of their disposal. In order to develop an inventory estimation method of difficult-to-measure LLFPs (Se-79, Tc-99, Sn-126, and Cs-135), a parametric study was carried out by using a sophisticated burnup calculation code and data. In the parametric study, fuel specifications and irradiation conditions are changed in the conceivable range. The considered parameters are fuel assembly types (PWR / BWR), U-235 enrichment, moderator temperature, void fraction, power density, and so on. From the calculated results, we clarify the burnup characteristics of the target LLFPs and their possible ranges of generations. Finally, candidates of the key nuclide are proposed for the scaling factor method of HLW.

Journal Articles

Measurement of DT and DD neutrons with a TOF spectrometer for determination of fuel ion density ratio in ITER

Okada, Koichi*; Kondo, Keitaro; Ochiai, Kentaro; Sato, Satoshi; Konno, Chikara; Okamoto, Atsushi*; Kobuchi, Takashi*; Kitajima, Sumio*; Sasao, Mamiko*

Journal of Plasma and Fusion Research SERIES, Vol.8, p.666 - 669, 2009/09

Measurement of fuel ion density ratio, $$n$$$$_{rm D}$$/$$n$$$$_{rm T}$$, is required for burning control on ITER. The measured $$n$$$$_{rm D}$$/$$n$$$$_{rm T}$$ ratio must be fed back in real time. A neutron measurement system to measure $$n$$$$_{rm D}$$/$$n$$$$_{rm T}$$ should be operable at high counting rate. It is estimated that the number of emitted DT neutrons is 200 times higher than that of DD neutrons under the condition of ITER standard operation. A neutron measurement system was developed using a DT/DD generator, where DT neutrons are dominant and DD neutrons are contaminated slightly in the neutron beam. The measurement instrument was a TOF spectrometer. Signals originating from each neutron must be distinguished in order to measure the fuel ratio. We developed a circuit system with discrimination windows to distinguish each signal pulse, and DT and DD neutrons were measured separately and simultaneously with this system. The experimental result indicates a possibility that this system is suitable for measurement of fuel ion density ratio on ITER.

Journal Articles

Viscosity of molten rare earth trichlorides

Hayashi, Hirokazu; Okamoto, Yoshihiro; Ogawa, Toru; Sato, Yuzuru*; Yamamura, Tsutomu*

Molten Salt Forum, 5-6, p.257 - 260, 1998/00

no abstracts in English

Oral presentation

Development of the method of fuel ratio measurement with neutron measurement planned on ITER experiments

Okada, Koichi; Kondo, Keitaro; Ochiai, Kentaro; Sato, Satoshi; Konno, Chikara; Nishitani, Takeo; Nomura, Ken*; Okamoto, Atsushi*; Kitajima, Sumio*; Sasao, Mamiko*

no journal, , 

no abstracts in English

Oral presentation

Measurement of neutron for particles control in burning plasma

Okada, Koichi*; Kondo, Keitaro; Ochiai, Kentaro; Sato, Satoshi; Konno, Chikara; Okamoto, Atsushi*; Kobuchi, Takashi*; Kitajima, Sumio*; Sasao, Mamiko*

no journal, , 

no abstracts in English

Oral presentation

Development of the ORIGEN2 library for LWR based on the latest nuclear data JENDL-4.0

Okumura, Keisuke; Kojima, Kensuke; Okamoto, Tsutomu

no journal, , 

New ORIGEN2 libraries (ORLIBJ40) for LWR were developed based on the latest Japanese nuclear data library JENDL-4.0. From post-irradiation examination analyses using ORLIBJ40, it was found that the new libraries improves the accuracy of spent nuclear fuel composition compared with conventional libraries, especially for MA nuclides, such as Np-237, Am and Cm isotopes, fission products sensitive to cross sections, such as Eu and Sm isotopes, and long-lived fission products like Se-79.

Oral presentation

Application of local power history normalization function to fuel assembly burn-up calculation

Okumura, Keisuke; Okamoto, Tsutomu

no journal, , 

In order to evaluate nuclide inventories in LWR spent fuels with sufficient accuracy, the local power history normalization function was newly implemented in the burn-up calculation code MVP-BURN. The function was validated by comparison between calculated and measured values for nuclide inventories in the post irradiation examination analyses.

Oral presentation

Inventory estimation of gadolinium in LWR spent fuel assembly

Kojima, Kensuke; Okumura, Keisuke; Okamoto, Tsutomu

no journal, , 

For the accurate inventory estimation of gadolinium isotopes in LWR fuel assemblies with burnable poisoned rods (Gd$$_{2}$$O$$_{3}$$-UO$$_{2}$$), burn-up analyses were carried out for PWR and BWR fuel assemblies by using MVP-BURN and JENDL-4.0. As a result, isotope generation and depletion of gadolinium in each fuel assembly were quantitatively clarified.

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