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photoproduction on the proton at 
= 1.3-2.4 GeVHashimoto, Toshikazu*; Tsuchikawa, Yusuke; LEPS BGOegg Collaboration*; 58 of others*
Physical Review C, 106(3), p.035201_1 - 035201_15, 2022/09
Times Cited Count：1 Percentile：0.02(Physics, Nuclear)Abe, Yuta; Tsuchikawa, Yusuke; Kai, Tetsuya; Matsumoto, Yoshihiro*; Parker, J. D.*; Shinohara, Takenao; Oishi, Yuji*; Kamiyama, Takashi*; Nagae, Yuji; Sato, Ikken
JPS Conference Proceedings (Internet), 33, p.011075_1 - 011075_6, 2021/03
Tsuchikawa, Yusuke; Abe, Yuta; Oishi, Yuji*; Kai, Tetsuya; Toh, Yosuke; Segawa, Mariko; Maeda, Makoto; Kimura, Atsushi; Nakamura, Shoji; Harada, Masahide; et al.
JPS Conference Proceedings (Internet), 33, p.011074_1 - 011074_6, 2021/03
In the decommissioning of the Fukushima-Daiichi (1F) Nuclear Power Plant, it is essential to understand characteristics of the melted core materials. The estimation of boride in the real debris is of great importance to develop safe debris removal plans. Hence, it is required to investigate the amount of boron in the melted core materials with nondestructive methods. Prompt gamma-ray activation analysis (PGAA) is one of the useful techniques to determine the amount of borides by means of the 478 keV prompt gamma-ray from neutron absorption reaction of boron. Moreover, it is well known that the width of the 478 keV gamma-ray peak is typically broadened due to the Doppler effect. The degree of the broadening is affected by coexisting materials, and can be recognized by the width of the prompt gamma-ray peak. As a feasibility study, the prompt gamma-ray from boride samples were measured using the ANNRI, NOBORU, and RADEN beamlines at the Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Complex (J-PARC).
Tsuchikawa, Yusuke; Kai, Tetsuya; Abe, Yuta; Oishi, Yuji*; Sun, Y.*; Oikawa, Kenichi; Nakatani, Takeshi; Sato, Ikken
Nuclear Instruments and Methods in Physics Research A, 991, p.164964_1 - 164964_5, 2021/03
Times Cited Count：0 Percentile：0.02(Instruments & Instrumentation)Peak shape analysis was performed for the energy spectra of Doppler-broadened prompt 
-rays generated by neutron capture reactions with various boride or boron samples. Significant differences were observed between nonmetallic and metallic borides. Minor differences between the peak shapes of prompt -rays from zirconium- and ferro-borons were evaluated by a peak fitting method. The identification of zirconium- and ferro-borons and other types of borides was estimated.
Abe, Yuta; Tsuchikawa, Yusuke; Kai, Tetsuya; Matsumoto, Yoshihiro*; Parker, J. D.*; Shinohara, Takenao; Oishi, Yuji*; Kamiyama, Takashi*; Nagae, Yuji; Sato, Ikken
Proceedings of 2020 International Conference on Nuclear Engineering (ICONE 2020) (Internet), 6 Pages, 2020/08
Teshigawara, Makoto; Tsuchikawa, Yusuke*; Ichikawa, Go*; Takata, Shinichi; Mishima, Kenji*; Harada, Masahide; Oi, Motoki; Kawamura, Yukihiko*; Kai, Tetsuya; Kawamura, Seiko; et al.
Nuclear Instruments and Methods in Physics Research A, 929, p.113 - 120, 2019/06
Times Cited Count：15 Percentile：88.82(Instruments & Instrumentation)A nano-diamond is an attractive neutron reflection material below cold neutron energy. The total neutron cross section of a nano-diamond was derived from a neutron transmission measurement over the neutron energy range of 0.2 meV to 100 meV because total neutron cross section data were not available. The total cross section of a nano-diamond with particle size of approximately 5 nm increased with a decrease in neutron energy to 0.2 meV. It was approximately two orders of magnitude larger than that of graphite at 0.2 meV. The contribution of inelastic scattering to the total cross section was to be shown negligible small at neutron energies of 1.2, 1.5, 1.9, 2.6, and 5.9 meV in the inelastic neutron scattering measurement. Moreover, small-angle neutron scattering measurements of the nano-diamond showed a large scattering cross section in the forward direction for low neutron energies.
Tsuchikawa, Yusuke; Kai, Tetsuya; Shinohara, Takenao; Parker, J. D.*; Oikawa, Kenichi
no journal, ,
The characteristics of NOBORU and RADEN are discussed from a viewpoint of neutron imaging with higher energy neutrons. Then some results of imaging with neutrons between 0.5 eV and 
MeV are presented. The authors also introduce an activity of developing a neutron imaging detector based on a lithium glass scintillator and a multi-anode photomultiplier tube to obtain a high efficiency at higher energies.
Kai, Tetsuya; Tsuchikawa, Yusuke; Hiroi, Kosuke; Su, Y. H.; Segawa, Mariko; Parker, J. D.*; Matsumoto, Yoshihiro*; Hayashida, Hirotoshi*; Shinohara, Takenao; Oikawa, Kenichi
no journal, ,
Shinohara, Takenao; Kai, Tetsuya; Oikawa, Kenichi; Hiroi, Kosuke; Su, Y. H.; Nakatani, Takeshi; Seki, Yoshichika; Tsuchikawa, Yusuke; Hayashida, Hirotoshi*; Parker, J. D.*; et al.
no journal, ,
The Energy-Resolved Neutron Imaging System, RADEN, in the Materials and Life Science Experimental Facility (MLF) of J-PARC, has been constructed as the world's first dedicated instrument to the pulsed neutron imaging. RADEN is designed to conduct energy-resolved neutron imaging experiments like Bragg edge, resonance absorption and pulsed polarized neutron imaging by fully utilizing the short-pulsed neutron's nature, together with the conventional neutron radiography and tomography. The construction of RADEN was completed in 2014, and user operation was started from April 2015 after commissioning studies using the neutron beam. In addition to the user programs, the instrument group continues further technical developments for advanced energy-resolved neutron imaging and improving the performance of devices, especially the counting type imaging detectors.
Tsuchikawa, Yusuke; Abe, Yuta; Oishi, Yuji*; Kai, Tetsuya; Harada, Masahide; Oikawa, Kenichi; Matsumoto, Yoshihiro*; Parker, J. D.*; Shinohara, Takenao; Nagae, Yuji; et al.
no journal, ,
In the decommissioning of the Fukushima-Daiichi (1F) Nuclear Power Plant, it is essential to understand characteristics of the melted core materials. The estimation of boride in the real debris is of great importance to develop safe debris removal plans. Hence, it is required to investigate the amount of boron in the melted core materials with nondestructive methods. Prompt gamma-ray activation analysis (PGAA) is one of the useful techniques to determine the amount of borides by means of the 478 keV prompt gamma-ray from neutron absorption reaction of boron. Moreover, it is well known that the width of the 478 keV gamma-ray peak is typically broadened due to the Doppler effect. The degree of the broadening is affected by coexisting materials, and can be recognized by the width of the prompt gamma-ray peak. As a feasibility study, the prompt gamma-ray from boride samples were measured using the NOBORU, and RADEN beamlines at the Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Complex (J-PARC).
Abe, Yuta; Kai, Tetsuya; Tsuchikawa, Yusuke; Matsumoto, Yoshihiro*; Parker, J. D.*; Shinohara, Takenao; Oishi, Yuji*; Kamiyama, Takashi*; Nagae, Yuji; Sato, Ikken
no journal, ,
福島第一原子力発電所事故Fukushima Daiichi Nuclear Power Station Accident
Abe, Yuta; Kai, Tetsuya; Tsuchikawa, Yusuke; Matsumoto, Yoshihiro*; Parker, J. D.*; Shinohara, Takenao; Kamiyama, Takashi*; Oishi, Yuji*; Nagae, Yuji; Sato, Ikken
no journal, ,
no abstracts in English
Tsuchikawa, Yusuke; Kai, Tetsuya; Abe, Yuta; Oishi, Yuji*; Sun, Y.*; Oikawa, Kenichi; Nakatani, Takeshi; Sato, Ikken; Joseph, P.*; Matsumoto, Yoshihiro*
no journal, ,
In the decommissioning of the Fukushima Daiichi Nuclear Power Plant (NPP), the quantitative analysis of residual boron and borides in the reactor core and the identification of boron compound states are one of the important issues to be investigated. In this presentation, we report on the neutron energy-resolved analysis of boron samples irradiated with neutrons at J-PARC/MLF. We also investigated the possibility of identifying the compounds using peak broadening of the prompt gamma rays for each boride. The prompt gamma-ray peak-widths of metallic and non-metallic borides were significantly different from each other, while those of zirconium boride and iron boride were slightly different. The differences between these metal borides were measured and evaluated in detail by gamma-ray energy spectrum analysis. Finally, we will briefly introduce the current experiments and analysis results of our efforts toward two- and three-dimensional quantitative measurements using energy-analyzed two-dimensional detectors.
Miyazaki, Yasunori; Sato, Daisuke; Watanabe, So; Nakamura, Masahiro; Shibata, Atsuhiro; Nomura, Kazunori; Kai, Tetsuya; Tsuchikawa, Yusuke; Parker, J. D.*
no journal, ,
no abstracts in English
Tsuchikawa, Yusuke; Kai, Tetsuya; Shinohara, Takenao; Oikawa, Kenichi; Abe, Yuta; Oishi, Yuji*; Parker, J. D.*; Matsumoto, Yoshihiro*; Nagae, Yuji; Sato, Ikken
no journal, ,
no abstracts in English
Oba, Yojiro; Sasaki, Hirokazu*; Shinohara, Takenao; Tsuchikawa, Yusuke; Parker, J. D.*
no journal, ,
no abstracts in English
Shinohara, Takenao; Kai, Tetsuya; Oikawa, Kenichi; Su, Y. H.; Tsuchikawa, Yusuke; Hayashida, Hirotoshi*; Parker, J. D.*; Matsumoto, Yoshihiro*; Kiyanagi, Yoshiaki*
no journal, ,
Tsuchikawa, Yusuke; Kai, Tetsuya; Abe, Yuta; Oikawa, Kenichi; Joseph, P.*; Shinohara, Takenao; Sato, Ikken
no journal, ,
We developed a method to obtain the areal density distribution of boron, which has a large neutron cross section, by means of an energy resolved neutron imaging. Commonly in a measurement of elements with very high neutron sensitivity, the quantitative measurement becomes more difficult with the amount of element due to the neutron self-shielding effect. To avoid this effect, an energy-resolved method using known cross section data was attempted, and a quantitative imaging of such elements was demonstrated at the MLF of J-PARC. This presentation introduces a measurement of melted simulated-fuel assemblies obtained in the research of the Fukushima Daiichi Nuclear Power Plant after the severe accident. Energy-dependent neutron transmission rates of the samples were measured by a neutron imaging detector, and were analyzed to obtained the areal density of boron at each position.
Harada, Masahide; Oikawa, Kenichi; Tsuchikawa, Yusuke; Yamaguchi, Yuji; Haga, Katsuhiro
no journal, ,
In the spallation neutron source at Materials and Life Science Experimental Facility in J-PARC, a 3-GeV and 1-MW proton beam induces into a mercury target and the neutrons beam is provide to neutron instruments. The target vessels are regularly replaced due to pitting damage. The proton beam power is gradually increased to 800 kW as of June 2022, and the optimum proton beam profile is used depending on the beam power. Based on these observations, fixed-point measurements have been periodically carried out to observe the intensity of the neutrons supplied from the spallation neutron source under the same measurement conditions at NOBORU. In the fixed-point measurements, the activation method with gold foils (15x15x0.1mm
) was used to observe the absolute intensity of thermal neutrons with and without cadmium foil. The irradiation time was set to about 10 to 30 minutes in accordance with the proton beam intensity. The gamma-ray from irradiated foil was measured with a germanium detector, and the amount of activation was identified. As a result of the measurement, the thermal neutron intensity was slightly dependent on the proton beam intensity.
Shinohara, Takenao; Kai, Tetsuya; Oikawa, Kenichi; Su, Y. H.; Tsuchikawa, Yusuke; Hayashida, Hirotoshi*; Parker, J. D.*; Matsumoto, Yoshihiro*; Kiyanagi, Yoshiaki*
no journal, ,
