Riyana, E. S.*; Suda, Shoya*; Ishibashi, Kenji*; Matsuura, Hideaki*; Katakura, Junichi*; Sun, G. M.*; Katano, Yoshiaki
Journal of Nuclear Science and Technology, 56(5), p.369 - 375, 2019/05
Nuclear reactors produce a great number of electron antineutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may have information on fuel burn-up and may be detected in future with advanced measurement technology. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectra from various reactors such as typical PWR reactor and others types of reactors for comparison. Our result shows the electron antineutrino flux in the low energy region increases with burn-up of nuclear fuel by accumulated nuclides with low Q values in beta decay.
Okumura, Keisuke; Riyana, E. S.; Sato, Wakaei*; Maeda, Hirobumi*; Katakura, Junichi*; Kamada, So*; Joyce, M. J.*; Lennox, B.*
Progress in Nuclear Science and Technology (Internet), 6, p.108 - 112, 2019/01
In order to establish the prediction method of the dose rate distribution in the primary containment vessel (PCV) of the Fukushima Daiichi Nuclear Power Station, a series of calculations were carried out in the following way; (1) burnup calculation to obtain fuel composition at the time of accident, (2) activation calculation for the structural materials including impurities, (3) estimation of Cs contamination in PCV based on the result of severe accident analysis by IRID, (4) decay calculation of radioactive nuclides, (5) photon transport calculation to obtain dose rate distribution. After that, Cs concentration around the dry-well of 1F was modified to be consistent with locally measured dose rates in the PCV-investigation by IRID.
Kamada, So*; Kato, Michio*; Nishimura, Kazuya*; Nancekievill, M.*; Watson, S.*; Lennox, B.*; Jones, A.*; Joyce, M. J.*; Okumura, Keisuke; Katakura, Junichi*
Progress in Nuclear Science and Technology (Internet), 6, p.199 - 202, 2019/01
As a technology development to investigate the distribution of submerged fuel debris in the primary containment vessel (PCV) of the Fukushima Daiichi Nuclear Power Station, we are conducting development experiments of sonar system to be mounted in a compact ROV. The experiments were conducted in two types of water tanks with different depths, simulating the PCV, using sonar with different sizes, ultrasonic frequencies, and beam scanning method, and simulated fuel debris. As a result, we characterized the shape discrimination performance of the simulated debris, and the noise due to multi-path in narrow closed space.
Matsumura, Taichi; Nagaishi, Ryuji; Katakura, Junichi*; Suzuki, Masahide*
Nuclear Science and Engineering, 192(1), p.70 - 79, 2018/10
The gamma-scanning of SDS (submerged demineralizer system) vessel used as a typical vessel for decontamination of radioactive water at Three Mile Island Unit 2 (TMI-2) accident was simulated in the axial and radial directions of real and cylindrical-shaped vessels by using a Monte Carlo calculation code (PHITS) on the basis of the geometrical and compositional information of vessel and gamma-scanning available in the previous reports at the accident. In the axial simulation, the true distribution of radioactive Cs in the zeolite packed bed of vessel was successfully evaluated when a correction function derived from a virtual constant distribution of Cs was applied to the reported gamma-scanning profile. In the radial simulation, the virtual disk-formed and shell-formed sources of Cs displaced in the packed bed were clearly observed from the top and bottom views of vessel. This new radial gamma-scanning indicates that the radial localization of Cs could be well observed by measuring gamma-ray from the top view of vessel during storage. We further examined the radial gamma-scanning from the side view whether the radial localization of Cs can be confirmed in the normally existing gamma-scanning room or not.
Nancekievill, M.*; Jones, A. R.*; Joyce, M. J.*; Lennox, B.*; Watson, S.*; Katakura, Junichi*; Okumura, Keisuke; Kamada, So*; Kato, Michio*; Nishimura, Kazuya*
IEEE Transactions on Nuclear Science, 65(9), p.2565 - 2572, 2018/09
In order to contribute to the development of technology to search fuel debris submerged in water inside the primary containment vessel of the Fukushima Daiichi Nuclear Power Station, we are developing a remotely operated vehicle (ROV) system equipped with a compact radiation detector and sonar. A cerium bromide (CeBr) scintillator detector for dose rate monitoring and ray spectroscopy was integrated into ROV and experimentally validated with a Cs source, both in the conditions of laboratory and submerged. In addition, the ROV combined with the IMAGENEX 831L sonar could characterize the shape and size of a simulated fuel debris at the bottom of the water pool facility.
Nancekievill, M.*; Jones, A. R.*; Joyce, M. J.*; Lennox, B.*; Watson, S.*; Katakura, Junichi*; Okumura, Keisuke; Kamada, So*; Kato, Michio*; Nishimura, Kazuya*
Proceedings of 5th International Conference on Advancements in Nuclear Instrumentation Measurement Methods and their Applications (ANIMMA 2017) (USB Flash Drive), 6 Pages, 2017/06
We are developping a submersible ROV system, coupled with radiation detectors aimed at mapping the interior of the reactors at the Fukushima Daiichi Nuclear Power Station. To map the -ray intensity environment a cerium bromide (CeBr) inorganic scintillator detector sensitive to -rays has been incorporated into the ROV to measure -ray intensity and identify radioactive isotopes. The ROV is a cylindrical shape with a diameter of about 150 mm, and it have two end caps of five pumps each allowing control of the ROV in 5 degree of freedom. It is possible to directly replace the CeBr detector with a single crystal chemical vapour deposition (CVD) neutron detector with a Li convertor foil that is capable of mapping the thermal neutron flux.
Katakura, Junichi*; Minato, Futoshi
JAEA-Data/Code 2015-030, 97 Pages, 2016/03
JENDL Decay Data File 2015 (JENDL/DDF-2015) has been produced. The decay data of nuclides with mass numbers from 1 to 260 are included. The nuclides with unknown - and/or beta-emission are also included in order to keep decay chains. The data of 1,284 fission product nuclides with mass from 66 to 172 remain unchanged from JENDL/FPD-2011 except several corrections which had been claimed by users, and those of the newly added 1,953 nuclides are taken from ENSDF. Finally, the decay data of 3,237 nuclides including 244 stable nuclides were compiled as JENDL/DDF-2015 file.
Katakura, Junichi*; Minato, Futoshi; Ohgama, Kazuya
EPJ Web of Conferences (Internet), 111, p.08004_1 - 08004_5, 2016/03
The JENDL FP Fission Yield Data Library (JENDL/FPY-2011) was released in 2011. Although the data of the yield file are successfully applied to decay heat summation calculations, there have been reported some inadequacies when applied to delayed neutron related subjects. And also from sensitivity analyses of summation calculation, some fission yield data in the JENDL file have been claimed to have some problems. In order to remedy those problems some yield data of the JENDL file have been re-examined and revised. The following is one example. The yield data of Ge for thermal neutron fission of U is given to be 6.277 in JENDL/FPY-2011 which has been claimed to be too large. The re-examination and re-calculation of the fission yield data now give the new value of 3.437 which seems to be more reasonable. There are some other nuclides indicated by the sensitivity analyses. The process of the re-examination of those nuclides and the revised yield data will be presented in the workshop WONDER 2015.
Koura, Hiroyuki; Katakura, Junichi*; Tachibana, Takahiro*; Minato, Futoshi
JAEA-Conf 2015-003, p.147 - 152, 2016/03
A chart of the nuclides 2014 version is now preparing to be published from JAEA. This will be the latest successive version of the chart since 1977, and continues every (approximately) four years until 2010. These charts include decay data of isotopes as half-lives, decay modes, and some isomeric states. In addition, the periodic table of elements, fundamental physical constants, thermal neutron capture and fission cross sections are tabulated. The latest version is now compiled with recent experimental data until the end of June in 2014. In the compilation process, we improved in the following parts: (1) Neutron or proton-unbound nuclei in the lighter region. (2) Drawing the neutron and proton-drip lines, and a boundary line of -delayed neutron emission. (3) 1- or 2-proton-emission theoretical half-lives are added for unmeasured nuclei in addition to original three partial half-lives of -decay, -decay and spontaneous fission. We compiled totally 3150 nuclides, which were experimental identified including 2914 life-measured nuclei. We will show overview of the chart with some statistics and examples.
Okumura, Keisuke; Sugino, Kazuteru; Kojima, Kensuke; Jin, Tomoyuki*; Okamoto, Tsutomu; Katakura, Junichi*
JAEA-Data/Code 2012-032, 148 Pages, 2013/03
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 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 (Se, etc.), compared with other existing ORIGEN2 libraries.
JAEA-Data/Code 2011-025, 73 Pages, 2012/03
The decay and fission yield data of fission products were compiled as JENDL FP decay data file 2011 (JENDL/FPD-2011) and JENDL FP fission yields data file 2011 (JENDL/FPY-2011). After the release of the JENDL FP decay data file 2000 file which was released in 2000, new measured data have been accumulated and new TAGS (Total Absorption -ray Spectroscopy) data have been published. The JENDL/FPD-2011 file was then compiled to reflect the new measured data. In order to keep the consistency between the number of the nuclides contained, fission yields file, JENDL/FPY-2011 was also compiled. The decay heat calculations for various kinds of fissioning nuclides were performed to confirm the validity of the JENDL/FPD-2011 and JENDL/FPY-2011 files. The calculated results showed good agreement with the measured data. The uncertainty analyses of the decay heat calculation were carried out with the method of sensitivity analysis.
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
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 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.
Kiyanagi, Yoshiaki*; Kino, Koichi*; Furusaka, Michihiro*; Hiraga, Fujio*; Kamiyama, Takashi*; Kato, Kiyoshi*; Igashira, Masayuki*; Katabuchi, Tatsuya*; Mizumoto, Motoharu*; Oshima, Masumi; et al.
Journal of the Korean Physical Society, 59(2), p.1781 - 1784, 2011/08
The project of the comprehensive nuclear data research for the development of the advanced reactor systems had been executed successfully by eight organizations from 2005 to 2009. In this project, we constructed the pulsed neutron beamline that was aimed to obtain neutron capture cross-sections of long-lived fission products and minor actinides accurately. The energy spectra, spatial distributions, and pulses of the beam were studied by measurements and simulation calculations, and they were found to be consistent with those of the beamline design. In this paper, we present the overview of the project and the properties of the neutron beam provided by this beam line.
Nuclear Data Sheets, 112(3), p.495 - 705, 2011/03
The 1999 evaluation for A=125 mass chain has been revised using experimental results from decays and reactions. Adopted values for the level and decay properties are tabulated. Inconsistencies and discrepancies are noted. All data available before January 2010 has been considered.
Wrzosek-Lipska, K.*; Zieliska, M.*; Hadyska-Klek, K.*; Hatsukawa, Yuichi; Iwanicki, J.*; Katakura, Junichi; Kisieliski, M.*; Koizumi, Mitsuo; Kowalczyk, M.*; Kusakari, Hideshige*; et al.
International Journal of Modern Physics E, 20(2), p.443 - 450, 2011/02
The quadrupole shape evolution in heaviest stable Mo isotopes is studied in terms of the shape coexistence phenomenon occurrence in this region of nuclear chart. Quadrupole deformation parameters of the Mo isotopes in the low-lying (ground and excited) 0 states were deduced using Coulomb excitation method. In all cases rich sets of electromagnetic reduced matrix elements were determined using the GOSIA code and then analyzed using the Quadrupole Sum Rules formalism. Discussion of the experimental results in comparison with the predictions of microscopic calculations within the general quadrupole collective Bohr Hamiltonian model is presented for Mo.
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
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.
Okumura, Keisuke; Asai, Shiho; Hanzawa, Yukiko; Suzuki, Hideya; Toshimitsu, Masaaki; Inagawa, Jun; Katakura, Junichi; Shinohara, Nobuo; Kaneko, Satoru*; Suzuki, Kensuke*
Proceedings of Joint International Conference of 7th Supercomputing in Nuclear Application and 3rd Monte Carlo (SNA + MC 2010) (USB Flash Drive), 5 Pages, 2010/10
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 were developed for MVP-BURN. They were applied to three post irradiation examinations including inventory measurements of Se, Tc, Sn and Cs. One of them is new measurements performed by JAEA. From the PIE analyses, it is found that the new measurements by JAEA are consistent with the other PIE data obtained by different laboratory with different techniques. It is also confirmed that the present calculation results show good agreements with experimental ones for Se and Cs within about 10%. In contrast, amounts of Tc and Sn are overestimated by about up to 50%. These discrepancies are likely due to the effect of insoluble residue in the measurements and/or errors of fission yields in the analyses.
Namekawa, Masakazu; Katakura, Junichi
JAEA-Data/Code 2010-017, 822 Pages, 2010/09
Neutron cross sections of 406 nuclides in JENDL-4.0 are presented in figures and tables. In the tables, shown are cross sections at 0.0253 eV and 14 MeV, Maxwellian average cross sections (kT = 0.0253 eV), resonance integrals and fission spectrum average cross sections. In the figures, shown are three kinds of figures of cross section curves at 300 K.
Igashira, Masayuki*; Baba, Mamoru*; Watanabe, Yukinobu*; Katakura, Junichi; Suyama, Kenya
Nippon Genshiryoku Gakkai-Shi, 51(4), p.290 - 293, 2009/04
The nuclear data library is required for the research and development of the nuclear energy. The requirements include not only safety improvements associated with high burnup of light water reactors, utilization of MOX fuels, and criticality safety control implementation of burnup credit and so on, but also research and development of innovative nuclear power system such as nuclear transmutation with the ADS; these requirements demand high precision data for the nuclear cross sections of minor actinides and fission product nuclides, and for the fission yields. The most important users of the nuclear data will still be those in the nuclear energy field. Moreover, for those users in the fields of radiation application and radiological engineering, nuclear data are required to be expanded in quantity and upgraded in quality. In the globalization trend of nuclear power industries, the international standard of nuclear data library is anticipated. In order to reflect the technology developed by Japan in the international standard, we should have our own nuclear data library leading the world.
Takemoto, Noriyuki; Okumura, Keisuke; Katakura, Junichi; Nagao, Yoshiharu; Kawamura, Hiroshi
JAEA-Data/Code 2008-029, 24 Pages, 2009/02
The continuous energy cross section library for the Monte Carlo transport code MCNP, JAC08T1, has been generated from the latest version of Japanese evaluated nuclear data library JENDL/AC released in March, 2008. The latest version of NJOY (NJOY99.259), the evaluated nuclear data processing system, has been employed to produce the library after necessary modifications in order to process JENDL/AC.