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Iwamoto, Hiroki; Nakano, Keita; Meigo, Shinichiro; Satoh, Daiki; Iwamoto, Yosuke; Ishi, Yoshihiro*; Uesugi, Tomonori*; Kuriyama, Yasutoshi*; Yashima, Hiroshi*; Nishio, Katsuhisa; et al.
JAEA-Conf 2022-001, p.129 - 133, 2022/11
For accurate prediction of neutronic characteristics for accelerator-driven systems (ADS) and a source term of spallation neutrons for reactor physics experiments for the ADS at Kyoto University Critical Assembly (KUCA), we have launched an experimental program to measure nuclear data on ADS using the Fixed Field Alternating Gradient (FFAG) accelerator at Kyoto University. As part of this program, the proton-induced double-differential thick-target neutron-yields (TTNYs) and cross-sections (DDXs) for iron have been measured with the time-of-flight (TOF) method. For each measurement, the target was installed in a vacuum chamber on the beamline and bombarded with 107-MeV proton beams accelerated from the FFAG accelerator. Neutrons produced from the targets were detected with stacked, small-sized neutron detectors composed of the NE213 liquid organic scintillators and photomultiplier tubes, which were connected to a multi-channel digitizer mounted with a field-programmable gate array (FPGA), for several angles from the incident beam direction. The TOF spectra were obtained from the detected signals and the FFAG kicker magnet's logic signals, where gamma-ray events were eliminated by pulse shape discrimination applying the gate integration method to the FPGA. Finally, the TTNYs and DDXs were obtained from the TOF spectra by relativistic kinematics.
Iwamoto, Hiroki; Nakano, Keita; Meigo, Shinichiro; Satoh, Daiki; Iwamoto, Yosuke; Sugihara, Kenta; Nishio, Katsuhisa; Ishi, Yoshihiro*; Uesugi, Tomonori*; Kuriyama, Yasutoshi*; et al.
Journal of Nuclear Science and Technology, 15 Pages, 2022/00
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Double-differential thick target neutron yields (TTNYs) for Fe, Pb, and Bi targets induced by 107-MeV protons were measured using the fixed-field alternating gradient accelerator at Kyoto University for research and development of accelerator-driven systems (ADSs) and fundamental ADS reactor physics research at the Kyoto University Critical Assembly (KUCA). Note that TTNYs were obtained with the time-of-flight method using a neutron detector system comprising eight neutron detectors; each detector has a small NE213 liquid organic scintillator and photomultiplier tube. The TTNYs obtained were compared with calculation results using Monte Carlo-based spallation models (i.e., INCL4.6/GEM, Bertini/GEM, JQMD/GEM, and JQMD/SMM/GEM) and the evaluated high-energy nuclear data library, i.e., JENDL-4.0/HE, implemented in the particle and heavy iontransport code system (PHITS). All models, including JENDL-4.0/HE, failed to predict high-energy peaks at a detector angle of 5
. Comparing the energy- and angle-integrated spallation neutron yields at energies of 
20 MeV estimated using the measured TTNYs and the PHITS indicated that INCL4.6/GEM would be suitable for the Monte Carlo transport simulation of ADS reactor physics experiments at the KUCA.
Tamai, Hiroshi; Mochiji, Toshiro; Senzaki, Masao*; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Dai-41-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2020/11
In light of recent delay of plutonium use in Japan and the increasing criticism of nuclear non-proliferation and nuclear security in the nuclear fuel cycle, the validity of these criticisms will be examined for the sustainable development of the nuclear fuel cycle policy. Issues on the view point of nuclear non-proliferation and nuclear security are examined.
Mochiji, Toshiro; Senzaki, Masao*; Tamai, Hiroshi; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Enerugi Rebyu, 40(8), p.56 - 57, 2020/07
Strict application of IAEA safeguards and nuclear security should be implemented for Japan's full-scale nuclear fuel cycle. Based on the knowledge and experience of research and development in the nuclear fuel cycle, nuclear material management, the effective and efficient promotion of new technologies should be promoted with scientific and demonstrative measures to strengthen the world's nuclear non-proliferation and nuclear security. Development or sophistication of new technologies, human resource development, and reinforcement of the international framework are future challenge in the international community.
Mochiji, Toshiro; Senzaki, Masao*; Tamai, Hiroshi; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Enerugi Rebyu, 40(7), p.58 - 59, 2020/06
Japan have promoted the peaceful use of plutonium with the nuclear non-proliferation commitment based on IAEA safeguards agreement and Japan-US nuclear cooperation agreement, as well as ensuring transparency of the policy that Japan has no plutonium without purpose of use. In promoting the nuclear fuel cycle, adherence to those measures and maintaining plutonium utilization by means of plutonium-thermal, and a fast reactor cycle to achieve large-scale and long-term energy supply and environmental improvement, therefore, further research and development is essential.
Mochiji, Toshiro; Senzaki, Masao*; Tamai, Hiroshi; Iwamoto, Tomonori*; Ishiguro, Yuzuru*; Kitade, Yuta; Sato, Heigo*; Suehiro, Rie*; Taniguchi, Tomihiro*; Fukasawa, Tetsuo*; et al.
Enerugi Rebyu, 40(6), p.58 - 59, 2020/05
In order to promote the peaceful use of nuclear energy, it is important not only to ensure safety but also to ensure nuclear non-proliferation and nuclear security. Japan has contributed to the international community through strengthening nuclear non-proliferation and nuclear security capabilities with technical and human resource development. However, in the wake of the accident at the Fukushima Daiichi Nuclear Power Plant in 2011, Japan's nuclear power plants have not restarted or plutonium use has not progressed smoothly. Concerns have been shown. Towards appropriate steps of Japan's nuclear fuel cycle policy, such concerns are examined and future efforts are summarized.
Iwamoto, Yosuke; Matsuda, Hiroki; Meigo, Shinichiro; Satoh, Daiki; Nakamoto, Tatsushi*; Yoshida, Makoto*; Ishi, Yoshihiro*; Kuriyama, Yasutoshi*; Uesugi, Tomonori*; Yashima, Hiroshi*; et al.
Proceedings of 61st ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams (HB 2018) (Internet), p.116 - 121, 2018/07
The radiation damage model in the radiation transport code PHITS has been developed to calculate the basic data of the radiation damage including the energy of the target Primary Knock on Atom (PKA). For the high-energy proton incident reactions, a target PKA created by the secondary particles was more dominant than a target PKA created by the projectile. To validate the radiation damage model in metals irradiated by 
100 MeV protons, we developed a proton irradiation device with a Gifford-McMahon cryocooler to cryogenically cool wire samples. By using this device, the defect-induced electrical resistivity changes related to the DPA cross section of copper and aluminum were measured under irradiation with 125 and 200 MeV protons at cryogenic temperature. A comparison of the experimental data with the calculated results indicates that the DPA cross section with defect production efficiencies provide better quantitative descriptions.
Tazaki, Makiko; Iwamoto, Tomonori*; Suda, Kazunori; Shimizu, Ryo; Tamai, Hiroshi; Kokaji, Lisa
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
As to states determination on physical protection measures of nuclear material and nuclear facilities against unauthorized removal of nuclear material, International Atomic Energy (IAEA) makes recommendation of states to follow a Table which sets out three different categories-based physical protection measures. Primary factors of such categories are isotope, quantity and radiation of nuclear material. On the other hand, in the US, attractiveness of nuclear material including physical form and degree of dilution of special nuclear material (SNM) are also primary determining factors of physical protection measures, in addition to IAEAs primary factors. Focusing on SMN within radioactive waste, authors carried out a study on optimization of physical protection measures for the radioactive waste, using the IAEA Implementing Guide and the US regulations as references.
Iwamoto, Yosuke; Yoshiie, Toshimasa*; Yoshida, Makoto*; Nakamoto, Tatsushi*; Sakamoto, Masaaki*; Kuriyama, Yasutoshi*; Uesugi, Tomonori*; Ishi, Yoshihiro*; Xu, Q.*; Yashima, Hiroshi*; et al.
Journal of Nuclear Materials, 458, p.369 - 375, 2015/03
Times Cited Count：11 Percentile：70.49(Materials Science, Multidisciplinary)To validate Monte Carlo codes for the prediction of radiation damage in metals irradiated by 100 MeV protons, defect-induced electrical resistivity changes of copper related to the displacement cross-section were measured with 125 MeV proton irradiation at 12 K. The cryogenic irradiation system was developed with a Gifford-McMahon cryocooler to cool the sample via an oxygen-free high-conductivity copper plate by conduction cooling. The sample was a copper wire with a 250
m diameter and 99.999% purity sandwiched between two aluminum nitride ceramic sheets. The resistivity increase did not change during annealing after irradiation below 15 K. The experimental displacement cross-section for 125 MeV irradiation shows similar results to the experimental data for 1.1 and 1.94 GeV. Comparison with the calculated results indicated that the defect production efficiency in Monte Carlo codes gives a good quantitative description of the displacement cross-section in the energy region 100 MeV.
Mukai, Yasunobu; Nakamura, Hironobu; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-32-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2011/11
JNFL and JAEA are collaboratively developing an advanced solution monitoring and measurement system (ASMS) that is direct Pu measurement NDA system in the solution tank containing plutonium nitrate solution for the improvement of current safeguards subjects to be solved, and for next generation safeguards instrument. The target measurement uncertainty of ASMS is set less than 6% that is equivalent to detection level of partial defect at interim inventory verification by NDA. The ASMS detector was designed based on MCNPX calculation, and then manufactured. As an actual test, the detector was set in a process tank at Plutonium Conversion Development Facility, the calibration tests (known-alpha) for quantitative measurement was conducted. As a result, the total measurement uncertainty for Pu mass is about 3.4% except for the low liquid height region that is satisfied the target value. In addition, the monitoring capability of ASMS was confirmed.
Nakamura, Hironobu; Mukai, Yasunobu; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
Proceedings of INMM 52nd Annual Meeting (CD-ROM), 9 Pages, 2011/07
JNFL and JAEA are collaboratively developing an Advanced Solution Measurement and monitoring System (ASMS) that is direct Pu measurement NDA system in the large scale solution tank containing purified plutonium nitrate for the improvement of current safeguards subjects to be solved, and for next generation safeguards instrument (NGSI). In this report, we summarize the first step results of ASMS development regarding quantitative measurement methodology. In order to establish quantitative measurement, accurate MCNPX modeling and calculations are very important and necessary. After calibration exercise implementation, we successfully obtained calibration constants (slope), and the total measurement uncertainty was about 3% for 
Pu effective mass for 2 hours measurement except for the low level region. In addition, the image of safeguards by design and collaboration of SMMS are also presented.
Mukai, Yasunobu; Nakamura, Hironobu; Hosoma, Takashi; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
Proceedings of INMM 51st Annual Meeting (CD-ROM), 9 Pages, 2010/07
JNFL and JAEA are collaboratively developing an advanced solution monitoring and measurement system (ASMS) for Rokkasho Reprocessing Plant (RRP). In this study, as a second trial, we designed and fabricated a new demonstration-type detector for ASMS, then installed it to another process tank in PCDF. Using two detectors, tests for process monitoring capability were performed for several operational conditions such as sampling, bubbling, circulation, solution transfer between two tanks, followed by studies in sensitivity of monitoring and studies in stability for the duration of storage. As a result, excellent performances and advantages of ASMS compared with conventional SMMS were confirmed. It is concluded that ASMS can provide very useful information of operation status and Pu amount shared between operator and inspector. It is sure that the combination of current SMMS and the ASMS is very powerful tool to improve transparency in the future safeguards design.
Nakamura, Hironobu; Takaya, Akikazu; Mukai, Yasunobu; Hosoma, Takashi; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-30-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2009/11
JNFL and JAEA have collaboratively started to develop an ASMS for RRP since 2007. The purpose of the development is to establish direct plutonium mass measurement technique by NDA of high concentrated pure plutonium nitrate solution in a strategic process tank. If it is established, ASMS provides direct Pu mass measurement and monitoring capability, substitutes for sampling and destructive analysis at IIV, and extends process monitoring to safety purposes. The target of the measurement uncertainty is set less than 6% which is equivalent to the detection level of partial defect at IIV by NDA. The principle is similar to the one of NDA for MOX powder, but extended such as introducing variable alpha depends on solution properties. As a first trial, a simple prototype system was constructed and calibrated at PCDF (Plutonium Conversion Development Facility) using plutonium nitrate solution. Consequently, good consistency between MCNP (Monte Carlo Neutron and Photon Transport Code) calculation and measured singles/doubles count rate were obtained. As a feasibility study, it was necessary to find out subjects to be solved. We would like to present benefits of ASMS, review installation and detector setup and summarize preliminary calibration results.
Nakamura, Hironobu; Takaya, Akikazu; Mukai, Yasunobu; Hosoma, Takashi; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
Proceedings of INMM 50th Annual Meeting (CD-ROM), 9 Pages, 2009/00
JNFL and JAEA have collaboratively started to develop an ASMS for RRP since 2007 as a trial base. The purpose of the development is to establish quantitative plutonium mass measurement technique directly by NDA of high concentrated pure plutonium nitrate solution in a process tank. If it is established, ASMS provides direct Pu mass measurement and monitoring capability, substitutes for sampling and analysis at IIV, and extends process monitoring to safety purposes. The target of the measurement uncertainty is set less than 6% (1 
) which is equivalent to the detection level of partial defect at IIV by NDA. The principle is similar to the one of NDA for MOX powder, but extended such as introducing variable alpha depends on solution properties. As a first trial, a simple prototype system was constructed and tested at Plutonium Conversion Development Facility of JAEA. Prior to the installation, MCNP calculations for entire cell and tank were performed. Two detectors with a gap were installed just center of the annular tank, then we carried out calibration using plutonium nitrate solution in the range up to 52 kgPu. Consequently, good consistency between calculation and measured singles/doubles count rate were obtained. As a feasibility study, it was necessary to find out subjects to be solved. We would like to present benefits of ASMS, review installation and detector setup and summarize preliminary calibration results.
Nakamura, Hironobu; Takaya, Akikazu; Mukai, Yasunobu; Hosoma, Takashi; Yoshimoto, Katsunobu; Tamura, Takayuki*; Iwamoto, Tomonori*
no journal, ,
JNFL and JAEA have collaboratively started to develop an ASMS for RRP since 2007. The purpose of the development is to establish direct plutonium mass measurement technique by NDA of high concentrated pure plutonium nitrate solution in a strategic process tank. If it is established, ASMS provides direct Pu mass measurement and monitoring capability, substitutes for sampling and destructive analysis at IIV, and extends process monitoring to safety purposes. The target of the measurement uncertainty is set less than 6%(1) which is equivalent to the detection level of partial defect at IIV by NDA. The principle is similar to the one of NDA for MOX powder, but extended such as introducing variable alpha depends on solution properties. As a first trial, a simple prototype system was constructed and tested at PCDF. Two detectors with a gap were installed just center of the annular tank, then we carried out calibration using plutonium nitrate solution (-52kgPu). Consequently, good consistency between MCNP calculation and measured singles/doubles count rate were obtained. As a feasibility study, it was necessary to find out subjects to be solved. We would like to present benefits of ASMS, review installation and detector setup and summarize preliminary calibration results.
Tanaka, Kenichi*; Fukahori, Tokio; Yamamoto, Masahiro; Sato, Tomonori; Motooka, Takafumi; Okumura, Keisuke; Shibata, Keiichi; Iwamoto, Nobuyuki
no journal, ,
The meaning and plan on development of standard and fundamental databases for material compositions and activation cross sections are introduced. Those database is important for estimation of radioactive nuclide production, which is necessary for safety management and waste estimation for disusing procedure of nuclear plants.
Iwamoto, Yosuke; Yoshida, Makoto*; Nakamoto, Tatsushi*; Ogitsu, Toru*; Yoshiie, Toshimasa*; Sakamoto, Masaaki*; Kuriyama, Yasutoshi*; Uesugi, Tomonori*; Ishi, Yoshihiro*; Mori, Yoshiharu*
no journal, ,
We measured the electrical resistivity under irradiation of 125 MeV proton in copper sample (0.2 um thickness) at cryogenic temperature at the FFAG accelerator facility in Kyoto university. Resistivity was measured by the four-terminal method. As a result, we measured the resistivity of copper at 7.3 K within 20 micro-ohm and temperature of sample. We measured the electrical resistivity under irradiation of 125 MeV proton in copper sample (0.2 um thickness) at cryogenic temperature at the FFAG accelerator facility in Kyoto university. Resistivity was measured by the four-terminal method. As a result, we measured the resistivity of copper at 7.3 K within 20 micro-ohm and temperature of sample.
Iwamoto, Yosuke; Yoshiie, Toshimasa*; Yoshida, Makoto*; Nakamoto, Tatsushi*; Sakamoto, Masaaki*; Kuriyama, Yasutoshi*; Uesugi, Tomonori*; Ishi, Yoshihiro*; Xu, Q.*; Yashima, Hiroshi*; et al.
no journal, ,
To validate the radiation damage calculation in the PHITS code for proton irradiation over 100 MeV, we have developed the device for electrical resistance measurement under cryogenic condition. A copper wire with 99.999% purity in a diameter of 250-m was set with a serpentine-shaped line on the AlN sheet which has high thermal conductivity and electric insulation. The sample was annealed for 1 h at 1,000C before irradiation. After annealing, the sample was cooled with an oxygen-free high-conductivity copper plate by conduction cooling. The electrical resistivity changes in the sample were measured using the four-probe technique. As a result, the residual resistivity ratio of the sample was about 1,800 between room temperature and 11 K. After 125 MeV proton irradiation with 1.45
10
(proton/cm
) at 11 K, the total resistance increase was 1.53 
, while the resistivity of copper before irradiation was 29.41 .
Iwamoto, Yosuke; Yoshiie, Toshimasa*; Yoshida, Makoto*; Nakamoto, Tatsushi*; Sakamoto, Masaaki*; Kuriyama, Yasutoshi*; Uesugi, Tomonori*; Ishi, Yoshihiro*; Xu, Q.*; Yashima, Hiroshi*; et al.
no journal, ,
To validate Monte Carlo code PHITS for the prediction of radiation damage in metals, the damage rate (defect-induced electrical resistivity changes / particle fluence) related to the displacement cross-section of copper were measured with 125 MeV proton irradiation under 12 K at the FFAG facility in the Kyoto University Research Reactor Institute. The sample was a copper wire with a 250-m diameter and 99.999% purity and was cooled by conduction cooling. After 125 MeV proton irradiation with 1.4510
protons/m at 12 K, the total resistivity increase was 4.9410
m (resistance increase: 1.53), while the resistivity of copper before irradiation was 9.49 10
m (resistance: 29.41). Comparison with other experimental results indicated that the damage rate by 125 MeV protons is almost same with those by 1.1 GeV protons and is higher than the damage rate by 14 MeV neutrons by a factor of 1.4. For the comparison with the PHITS results, the experimental data is smaller than the calculated result without the defect production efficiency by a factor of about 2.5 and that with the defect production efficiency by a factor of about 1.4, respectively. It indicates that the defect production efficiency in PHITS gives a good quantitative description of the displacement cross-section.
Iwamoto, Hiroki; Meigo, Shinichiro; Nishio, Katsuhisa; Ishi, Yoshihiro*; Hirose, Kentaro; Iwamoto, Yosuke; Kuriyama, Yasutoshi*; Maekawa, Fujio; Makii, Hiroyuki; Nakano, Keita; et al.
no journal, ,
no abstracts in English
