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Journal Articles

Introduction to nuclear security, 3; Nuclear material detection technique for nuclear security

Takahashi, Yoshiyuki*; Koizumi, Mitsuo

Nippon Genshiryoku Gakkai-Shi, 62(8), p.452 - 456, 2020/08

no abstracts in English

Journal Articles

Chapter 7, Research and development and international cooperation on nuclear non-proliferation and nuclear security

Tomikawa, Hirofumi; Koizumi, Mitsuo; Tamai, Hiroshi

Genshiryoku Heiwa Riyo To Kakufukakusan, Kakusekyuriti; NSA/Commentaries, No.25, p.167 - 174, 2020/06

Japan's efforts for research and development on nuclear material detection and nuclear forensics and international cooperation are introduced focusing on the various aspects implemented in JAEA.

Journal Articles

Testing enrichment meter based on nuclear resonance fluorescence

Omer, M.; Shizuma, Toshiyuki*; Hajima, Ryoichi*; Koizumi, Mitsuo

Nihon Kaku Busshitsu Kanri Gakkai Dai-40-Kai Nenji Taikai Puroshidhingusu, p.59 - 62, 2019/11

Journal Articles

Performance of large volume LaBr$$_{3}$$ scintillation detector equipped with specially-designed shield for neutron resonance capture analysis

Tsuchiya, Harufumi; Koizumi, Mitsuo; Kitatani, Fumito; Harada, Hideo

Nuclear Instruments and Methods in Physics Research A, 932, p.16 - 26, 2019/07

 Times Cited Count:0 Percentile:100(Instruments & Instrumentation)

Journal Articles

Development of active neutron NDA system for radioactive nuclear materials

Toh, Yosuke; Ozu, Akira; Tsuchiya, Harufumi; Furutaka, Kazuyoshi; Kitatani, Fumito; Komeda, Masao; Maeda, Makoto; Koizumi, Mitsuo

Proceedings of INMM 60th Annual Meeting (Internet), 7 Pages, 2019/07

Journal Articles

Delayed gamma-ray spectroscopy for nuclear material analysis, 2; Design of a practical system with DD neutron generator

Rossi, F.; Rodriguez, D.; Takahashi, Toon; Seya, Michio; Koizumi, Mitsuo

Proceedings of INMM 60th Annual Meeting (Internet), 7 Pages, 2019/07

Journal Articles

Model design of a compact delayed gamma-ray moderator system using $$^{252}$$Cf for safeguards verification measurements

Rodriguez, D.; Rossi, F.; Takahashi, Toon; Seya, Michio; Koizumi, Mitsuo

Applied Radiation and Isotopes, 148, p.114 - 125, 2019/06

 Times Cited Count:2 Percentile:28.85(Chemistry, Inorganic & Nuclear)

Journal Articles

Development of active non-destructive analysis technologies for nuclear nonproliferation and security of JAEA

Koizumi, Mitsuo

Proceedings of 41st ESARDA Annual Meeting (Internet), p.260 - 267, 2019/05

Journal Articles

Delayed gamma-ray spectroscopy, 2; Design study of moderator for a practical system

Rossi, F.; Rodriguez, D.; Takahashi, Toon; Seya, Michio; Koizumi, Mitsuo

Nihon Kaku Busshitsu Kanri Gakkai Dai-39-Kai Nenji Taikai Rombunshu (CD-ROM), 3 Pages, 2018/11

This paper (presentation) reports on the design study for seeking compactness of moderator (and reflector) structure for the Delayed Gamma-ray Spectroscopy Non Destructive Assay system to be applied for verification of fissile isotopic (Pu-239, Pu-241 and U-235) composition ratio in High Radioactive Nuclear Material sample such as dissolved solution of reprocessing facility. We first investigated advantages and disadvantages of using different compact neutron sources as DT and DD neutron generators. This led us to the conclusion of using DD sources to achieve a compact (and practical) NDA system. Based on MCNP simulations, with the use of a DD neutron generator, a preliminary optimization study was performed and will be shown here.

Journal Articles

Delayed gamma-ray spectroscopy, 1; Phase-I summary, Phase-II preview, and continuous solution monitoring

Rodriguez, D.; Rossi, F.; Takahashi, Toon; Seya, Michio; Koizumi, Mitsuo

Nihon Kaku Busshitsu Kanri Gakkai Dai-39-Kai Nenji Taikai Rombunshu (Internet), 2 Pages, 2018/11

Safeguards verification of high-radioactivity nuclear material (HRNM) solution samples is performed by HKED analysis for Pu/U element masses and time-consuming destructive analysis for isotopic compositions. To reduce the composition verification time, we have been collaborating with the EC-JRC to develop Delayed Gamma-ray Spectroscopy (DGS), which utilizes fission product $$gamma$$ rays with $$>$$ 3 MeV energy, above the intense passive background. We present the DGS Phase-I development summary and the Phase-II development plan. Additionally, we report about the $$gamma$$ ray pipe monitoring demonstration we performed at TRP and our process monitoring concept that includes GR pipe monitoring and self-interrogation DGS technique in reprocessing facilities.

Journal Articles

Development of differential die-away technique in an integrated active neutron NDA system for nuclear non-proliferation and nuclear security

Ozu, Akira; Maeda, Makoto; Komeda, Masao; Toh, Yosuke; Koizumi, Mitsuo; Seya, Michio

Proceedings of 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC 2017) (Internet), 4 Pages, 2018/11

Journal Articles

Delayed gamma-ray spectroscopy inverse Monte Carlo analysis method for nuclear safeguards nondestructive assay applications

Rodriguez, D.; Rossi, F.; Seya, Michio; Koizumi, Mitsuo

Proceedings of 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC 2017) (Internet), 3 Pages, 2018/11

Journal Articles

Dynamic nuclear self-polarization of III-V semiconductors

Koizumi, Mitsuo; Goto, Jun*; Matsuki, Seishi*

Journal of Semiconductors, 39(8), p.082001_1 - 082001_5, 2018/08

Dynamic nuclear self-polarization (DYNASP) is a phenomenon observed in III-V semiconductors. When electrons of the valence band of a semiconductor are optically excited to the conduction band, a relaxation process of the conduction electrons induces a large nuclear polarization to suddenly occur below a critical temperature. Extending the original theoretical work of Dyakonov et al., we examined the effect of spin distribution of valence electrons excited by the circularly polarized light and the effect of external magnetic field on the phenomenon of the nuclear self-polarization. We found that the nuclear polarization is achieved even above the critical temperatures by the effect of electron polarization and of the external magnetic field. To investigate the phenomenon experimentally, we constructed an apparatus for low-temperature experiments.

Journal Articles

Demonstration of $$gamma$$-ray pipe-monitoring capabilities for real-time process monitoring safeguards applications in reprocessing facilities

Rodriguez, D.; Tanigawa, Masafumi; Nishimura, Kazuaki; Mukai, Yasunobu; Nakamura, Hironobu; Kurita, Tsutomu; Takamine, Jun; Suzuki, Satoshi*; Sekine, Megumi; Rossi, F.; et al.

Journal of Nuclear Science and Technology, 55(7), p.792 - 804, 2018/07

 Times Cited Count:0 Percentile:100(Nuclear Science & Technology)

Nuclear material in reprocessing facilities is safeguarded by random sample verification with additional continuous monitoring applied to solution masses and volume in important tanks to maintain continuity-of-knowledge of process operation. Measuring the unique $$gamma$$ rays of each solution as the material flows through pipes connecting all tanks and process apparatuses could potentially improve process monitoring by verifying the compositions in real time. We tested this $$gamma$$ ray pipe-monitoring method using plutonium-nitrate solution transferred between tanks at the PCDF-TRP. The $$gamma$$ rays were measured using a lanthanum-bromide detector with a list-mode data acquisition system to obtain both time and energy of $$gamma$$-ray. The analysis and results of this measurement demonstrate an ability to determine isotopic composition, process timing, flow rate, and volume of solution flowing through pipes, introducing a viable capability for process monitoring safeguards verification.

Journal Articles

Development of active neutron NDA system for nuclear materials

Toh, Yosuke; Ozu, Akira; Tsuchiya, Harufumi; Furutaka, Kazuyoshi; Kitatani, Fumito; Komeda, Masao; Maeda, Makoto; Koizumi, Mitsuo; Heyse, J.*; Paradela, C.*; et al.

Proceedings of INMM 59th Annual Meeting (Internet), 9 Pages, 2018/07

Journal Articles

Development of detection and measurement technologies for Nuclear Non-proliferation and Security at JAEA

Koizumi, Mitsuo; Seya, Michio; Tomikawa, Hirofumi; Hori, Masato; Naoi, Yosuke

Proceedings of INMM 59th Annual Meeting (Internet), 8 Pages, 2018/07

no abstracts in English

Journal Articles

Development of delayed gamma-ray spectroscopy for nuclear material analysis

Rodriguez, D.; Rossi, F.; Takahashi, Toon; Seya, Michio; Koizumi, Mitsuo; Crochemore, J. M.*; Varasano, G.*; Bogucarska, T.*; Abbas, K.*; Pedersen, B.*

Proceedings of INMM 59th Annual Meeting (Internet), 7 Pages, 2018/07

Journal Articles

Delayed $$gamma$$-ray spectroscopy combined with active neutron interrogation for nuclear security and safeguards

Koizumi, Mitsuo; Rossi, F.; Rodriguez, D.; Takamine, Jun; Seya, Michio; Bogucarska, T.*; Crochemore, J.-M.*; Varasano, G.*; Abbas, K.*; Pedersen, B.*; et al.

EPJ Web of Conferences, 146, p.09018_1 - 09018_4, 2017/09

 Times Cited Count:2 Percentile:24.33

Journal Articles

Neutron resonance analysis for nuclear safeguards and security applications

Paradela, C.*; Heyse, J.*; Kopecky, S.*; Schillebeeckx, P.*; Harada, Hideo; Kitatani, Fumito; Koizumi, Mitsuo; Tsuchiya, Harufumi

EPJ Web of Conferences, 146, p.09002_1 - 09002_4, 2017/09

 Times Cited Count:3 Percentile:4.44

Journal Articles

Influence of the neutron transport tube on neutron resonance densitometry

Kitatani, Fumito; Tsuchiya, Harufumi; Koizumi, Mitsuo; Takamine, Jun; Hori, Junichi*; Sano, Tadafumi*

EPJ Web of Conferences, 146, p.09032_1 - 09032_3, 2017/09

 Times Cited Count:0 Percentile:100

335 (Records 1-20 displayed on this page)