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Ag(p,X) reaction at J-PARCSugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
JPS Conference Proceedings (Internet), 45, p.011181_1 - 011181_10, 2026/06
It is essential to estimate the residual gamma-ray dose rate at accelerator facilities, such as accelerator-driven system. Even though improvements of computer performance enabled us to predict nuclide production cross sections by physics models, the prediction accuracy of the models should be confirmed more. Thus, we have been measuring the nuclide production cross sections by the proton bombardment on various targets with activation technique at J-PARC. In this study, we measured nuclide production cross section of the Ag(p,X) reaction.
Collaborative Laboratories for Advanced Decommissioning Science; Hokkaido University*
JAEA-Review 2025-037, 103 Pages, 2025/12
JAEA-Review-2025-037.pdf:7.28MB
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2023. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2023, this report summarizes the research results of the "A study on the methodology for rational treatment/disposal of contaminated concrete waste considering volume reduction of waste" conducted in FY2023. The present study aims to evaluate rational waste management strategies incorporating reuse and recycling focusing on radioactive concrete waste, which will be massively generated from dismantling. Feasibility and challenges of aggregate recycling are considered assuming a typical recycled aggregate production technique, based on the characteristics of the concrete. In 2023, the migration behaviors of radionuclides and ions in cementitious materials having interfacial transition zones (ITZ) were investigated through diffusion and leaching experiments using radioactive and non-radioactive tracers and modeled by random walk particle tracking method with a sampling technique using a probabilistic distribution model for two media with an interface. Properties of surrogate contaminated concrete samples prepared by immersing in Cs solution were examined. Migration of ions was studied for surrogate contaminated aggregates and recycled concrete using the surrogate. In addition, surrogate waste package was prepared using by-product powder to study mechanical and chemical properties as well as leaching behavior of radionuclides. Information on properties of the contaminated concrete and tools to estimate the amount of concrete were organized in order to evaluate different waste management scenarios incorporating reuse/recycling.
Yamaguchi, Yuji; Niikura, Megumi*; Mizuno, Rurie*; Tampo, Motonobu*; Harada, Masahide; Kawamura, Naritoshi*; Umegaki, Izumi*; Takeshita, Soshi*; Haga, Katsuhiro
Nuclear Instruments and Methods in Physics Research B, 567, p.165801_1 - 165801_11, 2025/10
Times Cited Count：2 Percentile：66.26(Instruments & Instrumentation)As part of the development of a sample radioactivity calculation program, we have measured radionuclide production probabilities in negative muon nuclear capture to update experimental data and to validate a calculation dataset obtained by a Monte Carlo simulation code. The probabilities have been obtained by an activation experiment on 
Al, 
Si, 
Co, and Ta targets. The obtained probabilities expand the validation scope to the radionuclide production processes outside of the existing data coverage. By comparing the resultant probabilities with the calculated dataset, it has been revealed that the dataset is generally on the safe side in radioactivity estimation and needs to be corrected in the following three cases: (i) isomer production; (ii) radionuclide production by the multiple neutron emission; (iii) radionuclide production by particle emissions involving a proton. The present probabilities and the new findings on the correction provide valuable clues to improvements of the simulation models.
Mg, Si, Fe, Cu, and ZnSugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
Nuclear Instruments and Methods in Physics Research B, 549, p.165299_1 - 165299_12, 2024/04
Times Cited Count：1 Percentile：21.51(Instruments & Instrumentation)
Ti and 
Nb at 0.8 and 3.0 GeVSugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
Nuclear Instruments and Methods in Physics Research B, 545, p.165153_1 - 165153_9, 2023/12
Times Cited Count：2 Percentile：28.31(Instruments & Instrumentation)Ni and Zr at 0.4, 1.3, 2.2, and 3.0 GeVTakeshita, Hayato*; Meigo, Shinichiro; Matsuda, Hiroki*; Iwamoto, Hiroki; Nakano, Keita; Watanabe, Yukinobu*; Maekawa, Fujio
Nuclear Instruments and Methods in Physics Research B, 527, p.17 - 27, 2022/09
Times Cited Count：4 Percentile：41.30(Instruments & Instrumentation)To improve accuracy of nuclear design of accelerator driven nuclear transmutation systems and so on, nuclide production cross sections on Ni and Zr were measured for GeV energy protons. The measured results were compared with PHITS calculations, JENDL/HE-2007 and so on.
Meigo, Shinichiro; Nakano, Keita; Iwamoto, Hiroki
Purazuma, Kaku Yugo Gakkai-Shi, 98(5), p.216 - 221, 2022/05
For the realization of accelerator-driven transmutation systems (ADS) and the construction of the ADS target test facility (TEF-T) at J-PARC, it is necessary to study the proton beam handling technology and neutronics for protons in the GeV energy region. Accordingly, the Nuclear Transmutation Division of J-PARC has studied these issues with using J-PARC's accelerator facilities, and so on. This paper introduces these topics.
Nakano, Keita; Matsuda, Hiroki*; Meigo, Shinichiro; Iwamoto, Hiroki; Takeshita, Hayato*; Maekawa, Fujio
JAEA-Research 2021-014, 25 Pages, 2022/03
JAEA-Research-2021-014.pdf:2.1MB
For the development of accelerator-driven transmutation system (ADS), measurement of nuclide production cross-sections in proton-induced reactions on 
Be, C, Al, 
Sc, and V have been performed. The measured data are compared with the calculations by the latest nuclear reaction models and with the nuclear data library to investigate the reproducibilities.
Lu target irradiated with 0.4-, 1.3-, 2.2-, and 3.0-GeV protonsTakeshita, Hayato; Meigo, Shinichiro; Matsuda, Hiroki; Iwamoto, Hiroki; Nakano, Keita; Watanabe, Yukinobu*; Maekawa, Fujio
JAEA-Conf 2021-001, p.207 - 212, 2022/03
Prediction of nuclide production of spallation products by high-energy proton injection plays a fundamental and important role in shielding design of high-intensity proton accelerator facilities such as accelerator driven nuclear transmutation system (ADS). Since the prediction accuracy of the nuclear reaction models used in the production quantity prediction simulation is insufficient, it is necessary to improve the nuclear reaction models. We have measured nuclide production cross sections for various target materials with the aim of acquiring experimental data and improving nuclear reaction models. In this study, 1.3-, 2.2- and 3.0-GeV proton beams were irradiated to Lu target, and nuclide production cross-section data were acquired by the activation method. The measured data were compared with several nuclear reaction models used in Monte Carlo particle transport calculation codes to grasp the current prediction accuracy and to study how the nuclear reaction model could be improved.
Fe for 0.4-3.0 GeV protons in J-PARCMatsuda, Hiroki; Takeshita, Hayato*; Meigo, Shinichiro; Maekawa, Fujio; Iwamoto, Hiroki
JPS Conference Proceedings (Internet), 33, p.011047_1 - 011047_6, 2021/03
Accurate nuclide production cross-section data are required for the design of Accelerator-Driven nuclear transmutation System (ADS) such as the design of radioactive waste disposal, design of remote-handling procedure of highly activated components, and evaluation of exposure doses of rad-workers. Although much efforts have been devoted to nuclide production cross-section measurements so far, uncertainties of the measured data are sometimes large as several tens percentage, and there is no experimental data in the GeV energy region even for some of important nuclides. In this study, proton induced nuclide production cross-section of iron, which is the most important constituent element of steel, was measured. The present experiment was compared with calculations by the PHITS code with several physics models including Bertini and INCL4.6 and evaluated nuclear data JENDL-HE/2007. The most significant discrepancy found in this study was the production cross sections via the (p,xn) reaction. It was suggested that further improvements, such as the in-medium effect on the nucleon-nucleon scattering and the Pauli blocking, were required in the intra-nuclear cascade models used in this study.
Takeshita, Hayato; Meigo, Shinichiro; Matsuda, Hiroki; Iwamoto, Hiroki; Maekawa, Fujio; Watanabe, Yukinobu*
JPS Conference Proceedings (Internet), 33, p.011045_1 - 011045_6, 2021/03
To improve accuracy of nuclear design of accelerator driven nuclear transmutation systems, nuclide production cross sections on Ni and Zr, which were candidate materials to be used in ADS, were measured for GeV energy protons. The measured results were compared with PHITS calculations and JENDL/HE-2007.
Matsuda, Hiroki; Takeshita, Hayato*; Iwamoto, Hiroki; Meigo, Shinichiro
JAEA-Conf 2020-001, p.89 - 94, 2020/12
For the design of Accelerator-Driven nuclear transmutation System (ADS), accurate cross section data are required to estimate the number of radioactive nuclides for treating radioactive wastes in the ADS plant. Although much effort has been devoted to obtaining the nuclide production cross section irradiated by protons in the energy region utilized for the ADS at several facilities so far, data with systematic uncertainties of ~10% exist. Furthermore, no experimental data still exist around for protons in a few GeV region. In order to validate the calculation code and the evaluated data utilized for the ADS, we started the experiment to obtain the cross section at 3-GeV synchrotron in J-PARC. In this study, we obtained nuclide production cross section for targets with Z numbers from 26 to 30 (i.e. Fe, Ni, and Zn), which are important regions for the estimation of the radioactivity of the ADS structural materials. Furthermore, we investigated the incident energy dependency on the cross section from several hundred MeV to 3 GeV using the present and the previous experimental data, comparing with different intra-nuclear cascade and evaporation models of INCL4.6/GEM, INCL++/ABLA07, and Bertini/GEM, and evaluated nuclear data of JENDL-HE2007.
Takada, Hiroshi; Yoshizawa, Nobuaki*;
JAERI-Research 96-040, 91 Pages, 1996/08
JAERI-Research-96-040.pdf:2.2MB
no abstracts in English
-decay study of the T
=-1 nucleus 
Mn; J.Cerny*; R.Kirchner*; O.Klepper*; V.T.Koslowsky*; A.Plochocki*; E.Roeckl*; D.Schardt*; B.Sherrill*
GSI-86-1, P. 41, 1986/00
no abstracts in English
Takeshita, Hayato; Meigo, Shinichiro; Matsuda, Hiroki; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
For the purpose of improving nuclear design of high-energy and high-intensity proton accelerator facilities such as the accelerator-driven transmutation system (ADS), proton-induced nuclide production cross section was measured, and the results were compared with nuclear reaction models and evaluated nuclear data. We will report the nuclide production cross section for Ni which is used as the proton beam window material for ADS.
W(p,X) reactionSugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
Proton-induced nuclide production cross sections for tungsten in the GeV energy region were measured at the Japan Proton Accelerator Research Complex (J-PARC). The experimental values were compared with the literature values and the calculation results using the nuclear reaction model implemented in the radiation transport analysis code PHITS.
Mo production at the new J-PARC facilitySugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
Japan relies on imports for the supply of Mo/
Tc used in nuclear medicine examinations. However, due to the short half-life of Mo and its dependence on overseas conditions, domestic production is desirable. The 
Mo(n,
) method at JRR-3 is a candidate, but JRR-3 has a four-month shutdown period for maintenance, and a supply must be covered during that period. Therefore, a conceptual design for Mo production using a 0.4 GeV proton-induced nuclear reaction was developed at the new J-PARC facility, with the aim of covering the supply during the shutdown period. Additionally, we compared the Mo yield immediately after irradiation at the JRR-3 irradiation facility and discussed its usefulness at the new J-PARC facility and future challenges.
Pb(p,X) reactions at GeV-energy proton incidenceSugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
Nuclide production cross sections are key information to derive the residual -ray dose rate at accelerator facilities. In this study, we selected Pb as the target, which is planned to be contained in the neutron-production target and coolant at the ADS facility. We present the measurement of the nuclide production cross sections via the Pb(p,X) reactions at GeV-energy proton incidence. Additionally, the comparison among our present data, nuclear reaction models, and Japanese Evaluated Nuclear Data Library High Energy file 2007 is also presented to confirm the prediction accuracy.
Pb(p,X) reaction with GeV-energy proton incidenceSugihara, Kenta*; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
Estimation of residual gamma-ray dose rate is important from the viewpoint of radiation safety of accelerator driven systems (ADSs). Thus we measured the nuclide production cross sections via the Pb(p,X) reaction with GeV-energy at J-PARC. The advantage of J-PARC is that the proton intensity can be obtained with smaller uncertainty, due to a high-precision current transformer with an uncertainty of 2% (1-sigma). We present the measurement and measured excitation functions. In addition, comparison among the present data, results of nuclear reaction models, and evaluated nuclear data libraries are also reported.
Sugihara, Kenta; Meigo, Shinichiro; Iwamoto, Hiroki; Nakano, Keita; Maekawa, Fujio
no journal, ,
At the Japan Proton Accelerator Research Complex (J-PARC), nuclide production cross section of silicon for GeV-proton incidence was measured. The experimental results were compared with past experimental data, calculated results with the PHITS code and the evaluated nuclear data library JENDL/HE-2007. In addition, the results were compared with the results for aluminum of which atomic number is close to that silicon.
