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Journal Articles

Neutron transmission measurements for silica glass at the KURNS-LINAC

Lee, J.; Rossi, F.; Kodama, Yu; Hironaka, Kota; Koizumi, Mitsuo; Sano, Tadafumi*; Matsuo, Yasunori*; Hori, Junichi*

Annals of Nuclear Energy, 211, p.111017_1 - 111017_7, 2025/02

 Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)

Journal Articles

Evolution of radionuclide transport and retardation processes in uplifting granitic rocks, Part 2; Modelling coupled processes in uplift scenarios

Metcalfe, R.*; Benbow, S. J.*; Kawama, Daisuke*; Tachi, Yukio

Science of the Total Environment, 958, p.177690_1 - 177690_17, 2025/01

Uplifting fractured granitic rocks occur in substantial areas of countries such as Japan. A repository site would be selected in such an area only if it is possible to make a safety case, accounting for the changing conditions during uplift. The safety case must include robust arguments that chemical processes in the rocks around the repository will contribute sufficiently to minimise radiological doses to biosphere receptors. To provide confidence in the safety arguments, numerical models need to be sufficiently realistic, but also parameterised conservatively (pessimistically). However, model development is challenging because uplift involves many complex couplings between groundwater flow, chemical reactions between water and rock, and changing rock properties. The couplings would affect radionuclide mobilisation and retardation, by influencing diffusive radionuclide fluxes between groundwater flowing in fractures and effectively immobile porewater in the rock matrix and radionuclide partitioning between water and solid phases, via: (i) mineral precipitation/dissolution; (ii) mineral alteration; and (iii) sorption/desorption. It is difficult to represent all this complexity in numerical models while showing that they are parameterised conservatively. Here we present a modelling approach, illustrated by simulation cases for some exemplar radioelements, to identify realistically conservative process conceptualisations and model parameterisations.

Journal Articles

Potential of the young age reference materials; CA-ID-TIMS U-Pb dates of Cenozoic zircons in Japan

Nagata, Mitsuhiro; Fukuda, Shoma; Sueoka, Shigeru; Nakajima, Toru; Yokoyama, Tatsunori; Wall, C. J.*; Danhara, Toru*; Iwano, Hideki*; Tagami, Takahiro*

Fuisshon, Torakku Nyusureta, (37), p.11 - 13, 2024/12

In recent years, advances in analytical technology have made it possible to measure the U-Th-Pb dating of young geological units (e.g. $$<$$1 Ma). However, there are very few young standard samples available for evaluation. In this study, we attempted U-Pb dating using isotope dilution Thermal Ionization Mass Spectrometry (ID-TIMS) on young zircon samples (TRG04 and OGPK). As a result, we obtained preliminary U-Pb ages of 2.6654 $$pm$$ 0.0016 Ma and 1.1266 $$pm$$ 0.0014 Ma, respectively.

Journal Articles

Initial verification and validation of a new CASMO5 JENDL-5 nuclear data library for typical LWR applications

Watanabe, Tomoaki; Suyama, Kenya; Tada, Kenichi; Ferrer, R. M.*; Hykes, J.*; Wemple, C. A.*

Nuclear Science and Engineering, 198(11), p.2230 - 2239, 2024/11

 Times Cited Count:0 Percentile:0.00(Nuclear Science & Technology)

A new nuclear data library for the advanced lattice physics code CASMO5 has been prepared based on JENDL-5. In JENDL-5, many essential nuclides for conventional LWR analysis have also been modified based on state-of-the-art evaluations. The new JENDL-5-based CASMO5 library was prepared by replacing as much of the nuclear data of the current CASMO5 ENDF/B-VII.1-based library as possible with JENDL-5. This study verified and validated the new library. Verifications were performed based on the OECD/NEA burnup credit criticality safety benchmark phase III-C, and the calculated k$$_{rm inf}$$ and fuel compositions of the BWR fuel assembly were compared with reported benchmark results. Comparison with the MCNP6.2 result was also performed using the same benchmark model. In addition, the TCA critical experiment and Takahama-3 post-irradiation experiment were used for validation. The results indicate that the new library performs well and is comparable to the ENDF/B-VII.1-based library in predictions of reactivity and fuel compositions for LWR systems.

Journal Articles

Nonferroelectric phase with loss of cycloidal magnetic structure in Tb$$_{0.515}$$Gd$$_{0.485}$$Mn$$_{2}$$O$$_{5}$$

Ishii, Yuta*; Sakakura, Terutoshi*; Ishikawa, Yoshihisa*; Kiyanagi, Ryoji; Lustikova, J.*; Aoyama, Takuya*; Ogushi, Kenya*; Wakabayashi, Yusuke*; Kimura, Hiroyuki*; Noda, Yukio*

Physical Review B, 110(18), p.184404_1 - 184404_7, 2024/11

 Times Cited Count:0 Percentile:0.00(Materials Science, Multidisciplinary)

Journal Articles

Study on heat transfer behavior of a cylindrical particle bed with volumetric heating

Wen, J.*; Kamada, Yuto*; Yokoyama, Kosei*; Matsumoto, Tatsuya*; Liu, W.*; Morita, Koji*; Imaizumi, Yuya; Tagami, Hirotaka; Matsuba, Kenichi; Kamiyama, Kenji

Proceedings of 13th Korea-Japan Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS13) (Internet), 8 Pages, 2024/11

Journal Articles

Study on heat transfer behavior of a rectangular particle bed with volumetric heating

Wen, J.*; Kamada, Yuto*; Yokoyama, Kosei*; Matsumoto, Tatsuya*; Liu, W.*; Morita, Koji*; Imaizumi, Yuya; Tagami, Hirotaka; Matsuba, Kenichi; Kamiyama, Kenji

Proceedings of 31st International Conference on Nuclear Engineering (ICONE31) (Internet), 8 Pages, 2024/11

JAEA Reports

Heat transfer coefficients model for SIMMER-III and SIMMER-IV

Brear, D. J.*; Kondo, Satoru; Sogabe, Joji; Tobita, Yoshiharu*; Kamiyama, Kenji

JAEA-Research 2024-009, 134 Pages, 2024/10

JAEA-Research-2024-009.pdf:2.45MB

The SIMMER-III/SIMMER-IV computer codes are being used for liquid-metal fast reactor (LMFR) core disruptive accident (CDA) analysis. The sequence of events predicted in a CDA is often influenced by the heat exchanges between LMFR materials, which are controlled by heat transfer coefficients (HTCs) in the respective materials. The mass transfer processes of melting and freezing, and vaporization and condensation are also controlled by HTCs. The complexities in determining HTCs in a multi-component and multi-phase system are the number of HTCs to be defined at binary contact areas of a fluid with other fluids and structure surfaces, and the modes of heat transfer taking into account different flow topologies representing flow regimes with and without structure. As a result, dozens of HTCs are evaluated in each mesh cell for the heat and mass transfer calculations. This report describes the role of HTCs in SIMMER-III/SIMMER-IV, the heat transfer correlations implemented and the calculation of HTCs in all topologies in multi-component, multi-phase flows. A complete description of the physical basis of HTCs and available experimental correlations is contained in Appendices to this report. The major achievement of the code assessment program conducted in parallel with code development is summarized with respect to HTC modeling to demonstrate that the coding is reliable and that the model is applicable to various multi-phase problems with and without reactor materials.

Journal Articles

Production cross-sections of residual nuclides from $$^{93}$$Zr + $$p$$ at 27 MeV/nucleon

Hwang, J.*; Chillery, T.*; Dozono, Masanori*; Imai, Nobuaki*; Michimasa, Shinichiro*; Sumikama, Toshiyuki*; Chiga, Nobuyuki*; Ota, Shinsuke*; Nakayama, Shinsuke; 49 of others*

Progress of Theoretical and Experimental Physics (Internet), 2024(9), p.093D03_1 - 093D03_12, 2024/09

 Times Cited Count:0 Percentile:0.00(Physics, Multidisciplinary)

Nuclear transmutation emerges as a promising approach for reprocessing high-level waste, specifically treating long-lived nuclides like $$^{93}$$Zr from spent fuel. It is essential to accumulate reaction data for these nuclei to advance this prominent treatment and to build a comprehensive understanding of reaction mechanisms. In this study, the residual production cross-sections resulting from proton-induced reactions on $$^{93}$$Zr were measured at 27 MeV/nucleon in inverse kinematics. At the RIKEN-RIBF facility the OEDO beamline was used to deduce production cross-sections for isotopes, $$^{91-93}$$Nb, $$^{91,92}$$Zr, and $$^{88,89}$$Y. Comparing the results from this study and prior research with calculated excitation functions, a moderate agreement is found with theoretical predictions derived from TALYS and CCONE. Despite the potential limitations of low-energy proton-induced reactions for $$^{93}$$Zr transmutation, the measured cross-sections offer valuable insights for future considerations in nuclear-waste treatment facilities. This is particularly relevant for facilities exploring innovative methods, such as accelerator-driven systems.

Journal Articles

Development of a combined neutron resonance analysis technique as a nondestructive assay for fissile material quantification

Rossi, F.; Lee, J.; Kodama, Yu; Hironaka, Kota; Koizumi, Mitsuo; Hori, Junichi*; Terada, Kazushi*; Sano, Tadafumi*

Proceedings of 65th Annual Meeting of the Institute of Nuclear Materials Management (Internet), 8 Pages, 2024/07

Journal Articles

Existence of local polar domains in perovskite oxyfluoride, BaFeO$$_2$$F

Katsumata, Tetsuhiro*; Suzuki, Ryo*; Sato, Naoto*; Oda, Ryoya*; Motoyama, Shingo*; Suzuki, Shumpei*; Nakashima, Mamoru*; Inaguma, Yoshiyuki*; Mori, Daisuke*; Aimi, Akihisa*; et al.

Chemistry of Materials, 36(8), p.3697 - 3704, 2024/04

 Times Cited Count:0 Percentile:0.00(Chemistry, Physical)

A perovskite-type oxynitride BaFeO$$_2$$F was prepared by high-pressure synthesis. Since the SHG signal was observed in the obtained material, suggesting the existence of spontaneous polarization, the mechanism of polarization was investigated by synchrotron high-energy X-ray diffraction. The obtained pair distribution functions were fitted, and a local polarization mechanism with different orientations was found. Since BaFeO$$_2$$F is also a magnetic material, a magnetic domain and a ferroelectric domain are considered to coexist.

Journal Articles

Spin dependence in the $$p$$-wave resonance of $$^{139}$$$overrightarrow{textrm{La}}$+$overrightarrow{n}$

Okudaira, Takuya*; Nakabe, Rintaro*; Auton, C. J.*; Endo, Shunsuke; Fujioka, Hiroyuki*; Gudkov, V.*; Ide, Ikuo*; Ino, Takashi*; Ishikado, Motoyuki*; Kambara, Wataru*; et al.

Physical Review C, 109(4), p.044606_1 - 044606_9, 2024/04

 Times Cited Count:0 Percentile:0.00(Physics, Nuclear)

Journal Articles

High sensitivity of a future search for effects of $$P$$-odd/$$T$$-odd interactions on the 0.75 eV $$p$$-wave resonance in $$overrightarrow{n}$$+$$^{139}overrightarrow{textrm{La}}$$ forward transmission determined using a pulsed neutron beam

Nakabe, Rintaro*; Auton, C. J.*; Endo, Shunsuke; Fujioka, Hiroyuki*; Gudkov, V.*; Hirota, Katsuya*; Ide, Ikuo*; Ino, Takashi*; Ishikado, Motoyuki*; Kambara, Wataru*; et al.

Physical Review C, 109(4), p.L041602_1 - L041602_4, 2024/04

 Times Cited Count:0 Percentile:0.00(Physics, Nuclear)

Journal Articles

Crystal-liquid duality driven ultralow two-channel thermal conductivity in $$alpha$$-MgAgSb

Li, J.*; Li, X.*; Zhang, Y.*; Zhu, J.*; Zhao, E.*; Kofu, Maiko; Nakajima, Kenji; Avdeev, M.*; Liu, P.-F.*; Sui, J.*; et al.

Applied Physics Reviews (Internet), 11(1), p.011406_1 - 011406_8, 2024/03

 Times Cited Count:7 Percentile:96.91(Physics, Applied)

Journal Articles

Probing deformation behavior of a refractory high-entropy alloy using ${it in situ}$ neutron diffraction

Zhou, Y.*; Song, W.*; Zhang, F.*; Wu, Y.*; Lei, Z.*; Jiao, M.*; Zhang, X.*; Dong, J.*; Zhang, Y.*; Yang, M.*; et al.

Journal of Alloys and Compounds, 971, p.172635_1 - 172635_7, 2024/01

 Times Cited Count:1 Percentile:17.78(Chemistry, Physical)

Journal Articles

Improvement of the longitudinal phase space tomography at the J-PARC synchrotrons

Okita, Hidefumi; Tamura, Fumihiko; Yamamoto, Masanobu; Nomura, Masahiro; Shimada, Taihei; Saha, P. K.; Yoshii, Masahito*; Omori, Chihiro*; Sugiyama, Yasuyuki*; Hasegawa, Katsushi*; et al.

Journal of Physics; Conference Series, 2687(7), p.072005_1 - 072005_7, 2024/01

 Times Cited Count:0 Percentile:0.00(Physics, Atomic, Molecular & Chemical)

Longitudinal phase space tomography is an effective measurement tool for acquiring the longitudinal phase space distribution. For the J-PARC synchrotrons, tomography, which can take into account the beam dynamics such as longitudinal space charge effect and nonlinearity, is desired, as the beam power increases. In this study, for the J-PARC synchrotron, the CERN's tomography, which employs the hybrid algorithm that can consider the beam dynamics for reconstruction, is introduced and benchmarked. The benchmark results show that the CERN's tomography has the ability to measure the longitudinal phase space distribution accurately, in the high-power beam operation at the J-PARC synchrotrons.

Journal Articles

Stress corrosion cracking induced by the combination of external and internal hydrogen in Al-Zn-Mg-Cu alloy

Tang, J.*; Wang, Y.*; Fujihara, Hiro*; Shimizu, Kazuyuki*; Hirayama, Kyosuke*; Ebihara, Kenichi; Takeuchi, Akihisa*; Uesugi, Masayuki*; Toda, Hiroyuki*

Scripta Materialia, 239, p.115804_1 - 115804_5, 2024/01

 Times Cited Count:9 Percentile:72.83(Nanoscience & Nanotechnology)

Stress corrosion cracking (SCC) behaviors induced by the combination of external and internal hydrogen (H) in an Al-Zn-Mg-Cu alloy were systematically investigated via in situ 3D characterization techniques. SCC of the Al-Zn-Mg-Cu alloy could initiate and propagate in the potential crack region where the H concentration exceeded a critical value, in which the nanoscopic H-induced decohesion of $$eta$$-MgZn$$_2$$ precipitates resulted in macroscopic cracking. External H that penetrated the alloy from the environment played a crucial role during the SCC of the Al-Zn-Mg-Cu alloy by generating gradient-distributed H-affected zones near the crack tips, which made Al alloys in water environment more sensitive to SCC. Additionally, the pre-existing internal H was driven toward the crack tips during plastic deformation. It was involved in the SCC and made contributions to both the cracks initiation and propagation.

Journal Articles

A Raman spectroscopy study of bicarbonate effects on UO$$_{2+x}$$

McGrady, J.; Kumagai, Yuta; Watanabe, Masayuki; Kirishima, Akira*; Akiyama, Daisuke*; Kimuro, Shingo; Ishidera, Takamitsu

Journal of Nuclear Science and Technology, 60(12), p.1586 - 1594, 2023/12

 Times Cited Count:1 Percentile:34.39(Nuclear Science & Technology)

Journal Articles

Studying the impact of deuteron non-elastic breakup on $$^{93}$$Zr + d reaction cross sections measured at 28 MeV/nucleon

Chillery, T.*; Hwang, J.*; Dozono, Masanori*; Imai, Nobuaki*; Michimasa, Shinichiro*; Sumikama, Toshiyuki*; Chiga, Nobuyuki*; Ota, Shinsuke*; Nakayama, Shinsuke; 49 of others*

Progress of Theoretical and Experimental Physics (Internet), 2023(12), p.121D01_1 - 121D01_11, 2023/12

 Times Cited Count:2 Percentile:48.32(Physics, Multidisciplinary)

The deuteron is a loosely bound system which can easily break up into its constituent proton and neutron whilst in the presence of Coulomb and nuclear fields. Previous experimental studies have shown that this breakup process has a significant impact on residual nucleus production from deuteron bombardment in the high energy range of 50 - 210 MeV/nucleon. However, there remains a lack of cross-section data at energies below 50 MeV/nucleon. The current study determined $$^{93}$$Zr + d reaction cross sections under inverse kinematics at approximately 28 MeV/nucleon using the BigRIPS separator, OEDO beamline, and SHARAQ spectrometer. Cross sections from this research were compared with previous measurements and theoretical calculations. The experimental results show a large enhancement of the production cross sections of residual nuclei, especially those produced from a small number of particle emissions, compared to the proton-induced reaction data at similar bombarding energy. The DEURACS calculation, which quantitatively takes deuteron-breakup effects into account, reproduces the data well. As a long-lived fission product, $$^{93}$$Zr remains a challenge for nuclear waste disposal and treatment. This study's low-energy data may assist future consideration of nuclear-waste treatment facilities, where $$^{93}$$Zr + d may feasibly transmute the waste into short-lived/stable nuclei.

Journal Articles

Development of neutron resonance fission neutron analysis for nondestructive fissile material

Lee, J.; Kodama, Yu; Rossi, F.; Hironaka, Kota; Koizumi, Mitsuo; Hori, Junichi*; Sano, Tadafumi*

Dai-44-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2023/11

no abstracts in English

913 (Records 1-20 displayed on this page)