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6. Development of energy-resolved neutron imaging detectors at RADEN

Author

Parker, Joseph Don, Harada, Masahide, Hayashida, Hirotoshi, Hiroi, Kosuke, Kai, Tetsuya, Matsumoto, Yoshihiro, Nakatani, Takeshi, Oikawa, Kenichi, Segawa, Mariko, Shinohara, Takenao, Su, Yuhua, Takada, Atsushi, Takemura, Taito, Taniguchi, Tomoyuki, Tanimori, Toru, and Kiyanagi, Yoshiaki

Subjects
Physics - Instrumentation and Detectors
Abstract

Energy-resolved neutron imaging at a pulsed source utilizes the energy-dependent neutron transmission measured via time-of-flight to extract quantitative information about the internal microstructure of an object. At the RADEN instrument at J-PARC in Japan, we use cutting-edge detectors employing micro-pattern detectors or fast Li-glass scintillators and fast, all-digital data acquisition to perform such measurements, while continuing their development toward better utilization of the intense neutron source. In particular, for the Micro-Pixel Chamber based Neutron Imaging Detector ({\mu}NID), a micro-pattern detector with a 400 {\mu}m pitch and employing 3He for neutron conversion, we have successfully improved the spatial resolution from 200 to 100 {\mu}m, increased the detection efficiency from 18 to 26% for thermal neutrons, and increased the maximum count rate from 0.4 to 1 Mcps. We are also testing a new readout element with a 215 {\mu}m pitch for further improved spatial resolution, and a {\mu}NID with boron-based neutron converter for increased rate performance., Comment: 8 pages, 5 figures; accepted to Proceedings of International Conference on Neutron Optics 2017, Nara, Japan (JPS Conference Proceedings)

Published
2018
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10. Measurements of the Neutron Total and Capture Cross Sections and Derivation of the Resonance Parameters of 181Ta

Author

Endo, Shunsuke, Kimura, Atsushi, Nakamura, Shoji, Iwamoto, Osamu, Iwamoto, Nobuyuki, Rovira, Gerard, Toh, Yosuke, Segawa, Mariko, and Maeda, Makoto

Abstract

AbstractThe neutron total and capture cross sections of 181Ta were measured at the Accurate Neutron-Nucleus Research Measurement Instrument of the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Research Complex to improve the accuracy of the current resonance parameters. The total cross section was determined from the transmission measurement in the energy range from 0.2 to 150 eV. The capture cross section was derived from the capture yield using the pulse height weighting technique in the energy range from thermal to 150 eV. The thermal neutron capture cross section was measured as $$21.3 \pm 0.3(stat) \pm 0.6(sys)$$21.3±0.3(stat)±0.6(sys) b. The obtained transmission and capture cross section were simultaneously fitted using the resonance analysis code REFIT, and the resonance parameters for resonances below 150 eV were evaluated. The present resonance parameters were compared to reported measurements.

Published
2024
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13. Analytical Method for the determination At-211 using an α-Scintillation-Camera System and Thin-Layer Chromatography

Author

Segawa, Mariko, Nishinaka, Ichiro, Toh, Yosuke, Maeda, Makoto, and Ichiro, Nishinaka

Abstract

At-211 is artificially produced for medical purposes. To prevent severe loss of shortlived At-211, a rapid method analyzing both the radioactivity and all chemical forms was required for related fundamental researches. We propose a new method by means of an α-scintillation-camera system comprising of thin-layer chromatography and a high-sensitive CCD camera. The performance of the system was experimentally verified: low-radioactivity At-211 of 56 - 672 Bq was measured in a short-time of 1000 sec and all chemical forms of At-211 were evaluated. The results reveal that the method enables us to analyze two features of At-211 with significantly short-time.

Published
2020

14. Neutron capture and total cross-section measurements and resonance parameter analysis of niobium-93 below 400 eV

Author

Endo, Shunsuke, primary, Kimura, Atsushi, additional, Nakamura, Shoji, additional, Iwamoto, Osamu, additional, Iwamoto, Nobuyuki, additional, Rovira, Gerard, additional, Terada, Kazushi, additional, Meigo, Shin-ichiro, additional, Toh, Yosuke, additional, Segawa, Mariko, additional, Maeda, Makoto, additional, and Tsuneyama, Masayuki, additional

Published
2021
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16. Feasibility Study of PGAA for Boride Identification in Simulated Melted Core Materials

Author

Tsuchikawa, Yusuke, primary, Abe, Yuta, additional, Ohishi, Yuji, additional, Kai, Tetsuya, additional, Toh, Yosuke, additional, Segawa, Mariko, additional, Maeda, Makoto, additional, Kimura, Atsushi, additional, Nakamura, Shoji, additional, Harada, Masahide, additional, Oikawa, Kenichi, additional, Matsumoto, Yoshihiro, additional, Parker, Joseph D., additional, Shinohara, Takenao, additional, Nagae, Yuji, additional, and Sato, Ikken, additional

Published
2021
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19. The energy-resolved neutron imaging system, RADEN

Author

Shinohara, Takenao, primary, Kai, Tetsuya, additional, Oikawa, Kenichi, additional, Nakatani, Takeshi, additional, Segawa, Mariko, additional, Hiroi, Kosuke, additional, Su, Yuhua, additional, Ooi, Motoki, additional, Harada, Masahide, additional, Iikura, Hiroshi, additional, Hayashida, Hirotoshi, additional, Parker, Joseph D., additional, Matsumoto, Yoshihiro, additional, Kamiyama, Takashi, additional, Sato, Hirotaka, additional, and Kiyanagi, Yoshiaki, additional

Published
2020
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21. Neutron capture and total cross-section measurements and resonance parameter analysis of niobium-93 below 400 eV

Author

Endo, Shunsuke, Kimura, Atsushi, Nakamura, Shoji, Iwamoto, Osamu, Iwamoto, Nobuyuki, Rovira, Gerard, Terada, Kazushi, Meigo, Shin-ichiro, Toh, Yosuke, Segawa, Mariko, Maeda, Makoto, and Tsuneyama, Masayuki

Abstract

ABSTRACTNeutron capture yields and transmission ratios of 93Nb were measured by applying the time-of-flight method using the Accurate Neutron-Nucleus Reaction measurement Instrument of the Materials and Life Science Experimental Facility at the Japan Proton Accelerator Research Complex. Nb metal foils were used as samples. Germanium gamma-ray and Li-glass neutron detectors were used for capture yields and transmission ratio measurements, respectively. The pulse height weighting technique was applied to deduce the capture cross-sections from 0.01 to 400 eV, and the thermal-neutron capture cross-section was determined to be 0.97 ± 0.11 b. The total cross-sections were derived from transmission ratios ranging from 0.2 to 400 eV. The resonance parameters of 93Nb below 400 eV were determined based on the obtained capture cross-sections and transmission ratios using the resonance analysis code, REFIT, and compared with the parameters given by past measurements and the evaluated nuclear data library, JENDL-4.0.

Published
2022
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23. Development of Energy-Resolved Neutron Imaging Detectors at RADEN

Author

Don Parker, Joseph, primary, Harada, Masahide, additional, Hayashida, Hirotoshi, additional, Hiroi, Kosuke, additional, Kai, Tetsuya, additional, Matsumoto, Yoshihiro, additional, Nakatani, Takeshi, additional, Oikawa, Kenichi, additional, Segawa, Mariko, additional, Shinohara, Takenao, additional, Su, Yuhua, additional, Takada, Atsushi, additional, Takemura, Taito, additional, Taniguchi, Tomoyuki, additional, Tanimori, Toru, additional, and Kiyanagi, Yoshiaki, additional

Published
2018
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24. Analytical method for the determination of 211At using an α-scintillation camera system and thin-layer chromatography.

Author

Segawa, Mariko, Nishinaka, Ichiro, Toh, Yosuke, and Maeda, Makoto

Subjects
CHROMATOGRAPHIC analysis, SCINTILLATION counters, CAMERAS, RADIOACTIVITY, CCD cameras
Abstract

211At is artificially produced for medical purposes. To prevent severe loss of short-lived 211At, a rapid method analyzing both the radioactivity and all chemical forms was required for related fundamental researches. We propose a new method by means of an α-scintillation-camera system comprising of thin-layer chromatography and a high-sensitive CCD camera. The performance of the system was experimentally verified: low-radioactivity 211At of 56–672 Bq was measured in a short-time of 1000 s and all chemical forms of 211At were evaluated. The results reveal that the method enables us to analyze two features of 211At with significantly short-time. [ABSTRACT FROM AUTHOR]

Published
2020
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25. A Micro Pixel Chamber Based Neutron Imaging Detector with Boron Converter for Energy-Resolved Neutron Imaging at J-PARC

Author

Parker, Joseph D., primary, Harada, Masahide, additional, Hayashida, Hirotoshi, additional, Hiroi, Kosuke, additional, Kai, Tetsuya, additional, Matsumoto, Yoshihiro, additional, Oikawa, Kenichi, additional, Segawa, Mariko, additional, Shinohara, Takenao, additional, Su, Yuhua, additional, Takada, Atsushi, additional, Taniguchi, Tomoyuki, additional, Tanimori, Toru, additional, and Kiyanagi, Yoshiaki, additional

Published
2017
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26. Polarization analysis for magnetic field imaging at RADEN in J-PARC/MLF

Author

Shinohara, Takenao, primary, Hiroi, Kosuke, additional, Su, Yuhua, additional, Kai, Tetsuya, additional, Nakatani, Takeshi, additional, Oikawa, Kenichi, additional, Segawa, Mariko, additional, Hayashida, Hirotoshi, additional, Parker, Joseph D., additional, Matsumoto, Yoshihiro, additional, Zhang, Shuoyuan, additional, and Kiyanagi, Yoshiaki, additional

Published
2017
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27. Development of the next-generation micro pixel chamber-based neutron imaging detector (μNID) for energy-resolved neutron imaging at the J-PARC/MLF

Author

Parker, Joseph D., primary, Harada, Masahide, additional, Hayashida, Hirotoshi, additional, Hiroi, Kosuke, additional, Kai, Tetsuya, additional, Matsumoto, Yoshihiro, additional, Oikawa, Kenichi, additional, Segawa, Mariko, additional, Shinohara, Takenao, additional, Su, Yuhua, additional, Takada, Atsushi, additional, Zhang, Shuoyuan, additional, Tanimori, Toru, additional, and Kiyanagi, Yoshiaki, additional

Published
2016
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28. Neutron capture cross-section measurement and resolved resonance analysis of 237Np

Author

Rovira, Gerard, Katabuchi, Tatsuya, Tosaka, Kenichi, Matsuura, Shota, Terada, Kazushi, Iwamoto, Osamu, Kimura, Atsushi, Nakamura, Shoji, Iwamoto, Nobuyuki, Segawa, Mariko, and Maeda, Makoto

Abstract

ABSTRACTThe neutron capture cross-section of 237Np has been measured in the neutron energy region from 10 meV to 500 eV. A neutron time-of-flight method was employed using the NaI(Tl) spectrometer in the ANNRI beamline at the Japanese Proton Accelerator Research Complex (J-PARC). The experimental capture yield was derived using the pulse-height weighting technique and an energy-dependent cross-section was obtained relative to the incident neutron spectrum derived from a 10B(n, )7Li reaction yield. The absolute cross-section was determined by normalizing the results to JENDL-4.0 cross-section data at the first resonance of 237Np. The thermal cross-section was measured to be 177.6 ± 3.8 b. The resolved resonance region was analyzed with the REFIT code. An average radiation width = 40.3 ± 0.5 meV, a mean level spacing D0= 0.60 ± 0.02 eV and a neutron strength function 104S0= 1.02 ± 0.12 were obtained.

Published
2020
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29. Counting-type neutron imaging detectors of the energy-resolved neutron imaging system RADEN at the J-PARC/MLF

Author

Parker, Joseph D., primary, Harada, Masahide, additional, Hayashida, Hirotoshi, additional, Hiroi, Kosuke, additional, Kai, Tetsuya, additional, Matsumoto, Yoshihiro, additional, Nakatani, Takeshi, additional, Oikawa, Kenichi, additional, Segawa, Mariko, additional, Shinohara, Takenao, additional, Su, Yuhua, additional, Zhang, Shuoyuan, additional, Satoh, Setsuo, additional, and Kiyanagi, Yoshiaki, additional

Published
2015
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40. New Production Routes for Medical Isotopes 64Cu and 67Cu Using Accelerator Neutrons

Author

Kin, Tadahiro, Nagai, Yasuki, Iwamoto, Nobuyuki, Minato, Futoshi, Iwamoto, Osamu, Hatsukawa, Yuichi, Segawa, Mariko, Harada, Hideo, Konno, Chikara, Ochiai, Kentaro, and Takakura, Kosuke

Abstract

We have measured the activation cross sections producing 64Cu and 67Cu, promising medical radioisotopes for molecular imaging and radioimmunotherapy, by bombarding a natural zinc sample with 14 MeV neutrons. We estimated the production yields of 64Cu and 67Cu by fast neutrons from \text{natC($d$,$n$) with 40 MeV 5 mA deuterons. We used the present result together with the evaluated cross section of Zn isotopes. The calculated 64Cu yield is 1.8 TBq (175 g 64Zn) for 12 h of irradiation; the yields of 67Cu by 67Zn($n$,$p$)67Cu and 68Zn($n$,$x$)67Cu were 249 GBq (184 g 67Zn) and 287 GBq (186 g 68Zn) at the end of 2 days of irradiation, respectively. From the results, we proposed a new route to produce 67Cu with very little radionuclide impurity via the 68Zn($n$,$x$)67Cu reaction, and showed the 64Zn($n$,$p$)64Cu reaction to be a promising route to produce 64Cu. Both 67Cu and 64Cu are noted to be produced using fast neutrons.

Published
2013
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41. Measurements of the Neutron Total and Capture Cross Sections and Derivation of the Resonance Parameters of 181Ta.

Author

Endo, Shunsuke, Kimura, Atsushi, Nakamura, Shoji, Iwamoto, Osamu, Iwamoto, Nobuyuki, Rovira, Gerard, Toh, Yosuke, Segawa, Mariko, and Maeda, Makoto

Subjects
*NEUTRON measurement, *NEUTRON capture, *RESONANCE, *LIFE sciences, *THERMAL neutrons, *PROTON accelerators
Abstract

The neutron total and capture cross sections of 181Ta were measured at the Accurate Neutron-Nucleus Research Measurement Instrument of the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Research Complex to improve the accuracy of the current resonance parameters. The total cross section was determined from the transmission measurement in the energy range from 0.2 to 150 eV. The capture cross section was derived from the capture yield using the pulse height weighting technique in the energy range from thermal to 150 eV. The thermal neutron capture cross section was measured as $$21.3 \pm 0.3(stat) \pm 0.6(sys)$$ 21.3 ± 0.3 (stat) ± 0.6 (sys) b. The obtained transmission and capture cross section were simultaneously fitted using the resonance analysis code REFIT, and the resonance parameters for resonances below 150 eV were evaluated. The present resonance parameters were compared to reported measurements. [ABSTRACT FROM AUTHOR]

Published
2024
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42. LETTERS.

Author

Segawa, Mariko, Wilkin, Sam, Abedini, Hossien, Barton, David, Esteban, Aitor, Rice, John, and Huszar, Laszlo

Subjects
*LETTERS to the editor, *BASQUES, *EMPLOYEE selection, *POLITICAL participation
Abstract

Several letters to the editor are presented in response to articles in previous issues including "Will the Basques relent?," in the July 1996 issue, "A funny way to fill the world's top job," in the July 1996 issue, and the rejection of Iranians of the People's Mujahideen by Bahman Azadi in the August 1996 issue.

Published
1996

43. Nondestructive Quantitative Analysis of Difficult-to-Measure Radionuclides 107 Pd and 99 Tc.

Author

Toh Y, Segawa M, Maeda M, Tsuneyama M, Kimura A, Nakamura S, Endo S, and Ebihara M

Subjects
Gamma Rays, Half-Life, Humans, Radioisotopes, Neutrons, Radioactive Waste
Abstract

Considering the expanding demand for nuclear waste management of the spent nuclear fuel materials in near future, a nondestructive analytical scheme applicable to one of the most difficult-to-measure nuclides 107 Pd, which emits no decay γ-rays and whose half-life is too long to be decayed out during a human lifetime, was designed. The scheme consists of a sophisticated instrument capable of the detection of γ-rays by Ge detectors coupled with time-of-flight measurement of neutrons and a high-intensity pulsed neutron beam and can simultaneously perform time-of-flight-coupled prompt γ-ray analysis (TOF-PGA) as well as PGA and neutron resonance capture analysis (NRCA). The analytical capability for simulated samples of the Tc-platinum group metals (Tc-PGMs) obtained by the group-partitioning process of spent nuclear fuels, which contain not only 107 Pd but also 99 Tc and other difficult-to-measure fission products, was evaluated. It was confirmed that although PGA and NRCA can accurately analyze both nuclides in individual, single substances, only TOF-PGA can analyze 107 Pd as well as 99 Tc in the Tc-PGM-simulated sample. The TOF-PGA measurement technique can be widely used for the nondestructive analysis of 107 Pd and 99 Tc in nuclear wastes.

Published
2021
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