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Iwamoto, Hiroki; Nakano, Keita*; Meigo, Shinichiro; Takeshita, Hayato; Maekawa, Fujio
EPJ Web of Conferences, 284, p.01033_1 - 01033_4, 2023/05
Times Cited Count：0 Percentile：0.21(Nuclear Science & Technology)no abstracts in English
Takeshita, Hayato*; Meigo, Shinichiro; Matsuda, Hiroki*; Iwamoto, Hiroki; Nakano, Keita; Watanabe, Yukinobu*; Maekawa, Fujio
Nuclear Instruments and Methods in Physics Research B, 511, p.30 - 41, 2022/01
Times Cited Count：5 Percentile：65.59(Instruments & Instrumentation)Nuclide production cross sections for proton-induced reactions on Mn and Co at incident energies of 1.3, 2.2, and 3.0 GeV were measured by the activation method at the J-PARC. In total, 143 production cross sections of reaction products were obtained. Among them, the cross sections of 
Mn(p,X)
S and Mn(p,X)
Ar were measured for the first time. The stable proton beam and well established beam monitoring system contributed to the reduction of the systematic uncertainties to typically less than 5%, which was better than those of the previous data. To examine the prediction capabilities of spallation reaction models and evaluated data library, the measured data were compared with the spallation reaction models in PHITS (INCL4.6/GEM, etc.), INCL++/ABLA07, and the JENDL/HE-2007 library. The comparison of the mean square deviation factors indicated that both INCL4.6/GEM and JENDL/HE-2007 showed better agreement with the measured data than the others.
Iwamoto, Hiroki
Journal of Nuclear Science and Technology, 57(8), p.932 - 938, 2020/08
Times Cited Count：13 Percentile：86.19(Nuclear Science & Technology)We present a new approach to generate nuclear data from experimental cross section data by Gaussian process regression. This paper focuses on generating proton-induced nuclide production cross sections for nickel target. Our results provide reasonable fitting curves together with their uncertainties and suggest that this approach appears to be effective in generating or evaluating the nuclear data. Besides, our results suggest that our approach could be available for experimental design in terms of reducing the generated nuclear data uncertainty.
Takada, Hiroshi; Nakahara, Yasuaki; ; *; Yoshizawa, Nobuaki*
Proc. of NEA/NSC Specialists Meeting on Intermediate Energy Nuclear Data:Models and Codes, 0, p.121 - 136, 1994/00
no abstracts in English
Matsuda, Hiroki; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
For the improvement of nuclear design for Accelerator-Driven System (ADS), production cross section with higher accuracy is required. For data acquisition around 1 GeV energy range at J-PARC, protons having energy 0.8 and 3.0 GeV were irradiated on metal samples, which were sandwiched by several metal foils (0.1mm thickness). Analysis of the gold foils was started since there are many experimental data comparatively and is a monoisotopic element. Created activated nuclides were identified by germanium detectors. Finally, production cross sections were evaluated by irradiation parameters. They were compared with the evaluated data (JENDL-HE/2007) and the calculated one by PHITS code. It was found that the cross section of 
Sc agreed with JENDL-HE/2007 under 1.5 GeV region, it underestimated 50% above that region. The PHITS calculation underestimated drastically over whole energy range even though the GEM model which described an evaporation process were replaced by Furihata GEM model. For 
Os, namely spallation product, both the calculation and the evaluated data underestimated the data over the whole range. Thus, it was recommended that an intranuclear cascade model and an evaporation model implemented in PHITS should be modified.
Matsuda, Hiroki; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio
no journal, ,
For the improvement of nuclear design for Accelerator-Driven System (ADS), production cross section with higher accuracy is required. For data acquisition around 1 GeV energy range at J-PARC, protons having energy 0.4 to 3.0 GeV were irradiated on metal samples such as carbon and beryllium. Experiment and analysis methods were employed that were presented in the AESJ2018 autumn meeting. They were compared with the evaluated data (JENDL-HE/2007), the calculated one by PHITS code, and the one by the latest intranuclear cascade model INCL++ and a statistical decay model ABLA07. It was found that the cross section of 
and 
in this experiment has higher accuracy (approx. 7%) than other experiments due to precise beam control at J-PARC. JENDL/HE-2007 in which reaction is stored among light nuclides agreed with these results and other experiments within 9% uncertainty. PHITS calculation also showed a good agreement over the whole energy range. Especially PHITS in which the original GEM model was implemented, showed better agreement above 1 GeV range. Though the INCL++/ABLA07 calculations excellently agree with the experiments, the calculation overestimated over the whole range. In reaction, new experimental data were obtained around few GeV range. It was found that the calculation underestimated about 20 - 50% over the whole range.
Matsuda, Hiroki; Takeshita, Hayato*; Meigo, Shinichiro; Iwamoto, Hiroki
no journal, ,
For the improvement of nuclear design for Accelerator-Driven System (ADS), a production cross-section with higher accuracy is required. For data acquisition around 1 GeV energy range at J-PARC, protons in the energy region from 0.4 to 3.0 GeV were irradiated on Ag and Ta. Experiment and analysis methods were employed that were presented in the AESJ2018 autumn meeting. They were compared with the calculated data by PHITS code, and the one by the latest intranuclear cascade model INCL++ and a statistical decay model ABLA07. It was found that calculations for the 
Ag, 
Kr, and 
Be production cross-sections with INCL-4.6/GEM, Bertini/GEM, and INCL-6.0/ABLA07 could predict the experimental data within a factor 0.5 to 2. On the other hand, in the case of 
Na, 
Na, and 
Rh cross sections, all calculations showed huge overestimation or underestimation. In order to increase lighter nuclides such as Be and Na, we adopted a statistical multifragmentation model in the calculation. Although the calulcation was slightly improved still it has a large discrepancy in the experiment. Thus, a modification of the intra-nuclear cascade model was required, which is to be performed.
Iwamoto, Hiroki; Takeshita, Hayato*
no journal, ,
no abstracts in English
Iwamoto, Hiroki
no journal, ,
no abstracts in English
Iwamoto, Hiroki; Meigo, Shinichiro; Sugihara, Kenta*
no journal, ,
no abstracts in English
