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Journal Articles

Prospective features for integration of nuclear forensics capability in national framework

Tamai, Hiroshi; Okubo, Ayako; Kimura, Yoshiki; Shinohara, Nobuo; Tazaki, Makiko; Shimizu, Ryo; Suda, Kazunori; Tomikawa, Hirofumi

Proceedings of INMM 58th Annual Meeting (Internet), 6 Pages, 2017/07

Nuclear forensics is a technical measure to analyse and collate samples of illegally used nuclear materials, etc., to clarify their origins, routes, etc. and contribute to criminal identifications. Close collaboration with police and judicial organizations is essential. The national response framework is being built up with international cooperation. Discussions on promoting technical capability and regional cooperation are presented.

Journal Articles

Technical/institutional prerequisite for nuclear forensics response framework

Tamai, Hiroshi; Okubo, Ayako; Kimura, Yoshiki; Kokaji, Lisa; Shinohara, Nobuo; Tomikawa, Hirofumi

Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 8 Pages, 2017/02

Nuclear Forensics capability has been developed under the international collaborations. For its effective function, technical development in analysis of seized nuclear materials as well as the institutional development in comprehensive response framework are required under individual national responsibility. In order to keep the "chain of custody" in the proper operation of sample collection at the event scene, radiological analysis at the laboratory, storage of the samples, and further inspection and trial, close cooperation and information sharing between relevant organisations are essential. IAEA issues the Implementing Guide to provide the model action plan and assists individual national development. International cooperation for the technical improvement and awareness cultivation is promoted. Examples in such national developments will be introduced and prospective technical/institutional prerequisite for nuclear forensics response framework will be studied.

Journal Articles

Current status and achievements on nuclear forensics technology developments for nuclear security

Kimura, Yoshiki; Shinohara, Nobuo; Okubo, Ayako

Nihon Genshiryoku Gakkai-Shi ATOMO$$Sigma$$, 57(12), p.782 - 786, 2015/12

no abstracts in English

Journal Articles

Development of prototype national nuclear forensics library at Japan Atomic Energy Agency

Kimura, Yoshiki; Shinohara, Nobuo; Funatake, Yoshio

Proceedings of INMM 56th Annual Meeting (Internet), 8 Pages, 2015/07

JAEA Reports

Report on research and development of nuclear forensics technologies

Okubo, Ayako; Kimura, Yoshiki; Shinohara, Nobuo; Toda, Nobufumi; Funatake, Yoshio; Watahiki, Masaru; Sakurai, Satoshi; Kuno, Yusuke

JAEA-Technology 2015-001, 185 Pages, 2015/03

JAEA-Technology-2015-001.pdf:56.65MB

Nuclear forensics is the analysis of intercepted illicit nuclear or radioactive material and any associated material to provide evidence for nuclear attribution by determining origin, history, transit routes and purpose involving such material. Nuclear forensics activity includes sampling of the illicit material, analysis of the samples and evaluation of the attribution by comparing the analyzed data with database or numerical simulation. Because the nuclear forensics technologies specify the origin of the nuclear materials used illegal dealings or nuclear terrorism, it becomes possible to identify and indict offenders, hence to enhance deterrent effect against such terrorism. Worldwide network on nuclear forensics can contribute to strengthen global nuclear security regime. In this paper, the results of research and development of fundamental nuclear forensics technologies performed in Japan Atomic Energy Agency during the fiscal term of 2011-2013 were reported.

Journal Articles

Progress and future prospects of nuclear forensics technology development project at JAEA

Kimura, Yoshiki; Shinohara, Nobuo; Sato, Kaneaki; Toda, Nobufumi; Shinoda, Yoshiharu; Funatake, Yoshio; Watahiki, Masaru; Kuno, Yusuke

Proceedings of INMM 55th Annual Meeting (Internet), 7 Pages, 2014/07

In 2010, the Japan Government issued the national statement at Nuclear Security Summit (Washington D.C., USA) to develop technologies related to measurement and detection of nuclear materials for nuclear forensics within three-year timeframe, and to share the products with the international community in order to contribute to strengthening the nuclear security system. In response to this statement, JAEA that possesses sufficient technical capabilities to fulfil this nuclear forensics mission has started a nuclear forensics technology development project since JFY 2011. This paper will present the progress of the development project during JFY 2011 to 2013. This project includes the developments of analytical technologies such as isotope and impurity measurements, morphology analysis, age determination technique, and the prototype of national nuclear forensics library (NNFL). Some future prospects of this project will be also presented in this paper.

Journal Articles

Lessons learned from the international tabletop exercise of national nuclear forensics library at JAEA

Kimura, Yoshiki; Shinohara, Nobuo; Funatake, Yoshio

Journal of Nuclear Materials Management, 42(4), p.40 - 45, 2014/00

Japan Atomic Energy Agency (JAEA) has initiated an R&D project on nuclear forensics technology from 2011. This project includes development of prototype national nuclear forensics library (NNFL), and the JAEA attended to the first international table top exercise of NNFL "Galaxy Serpent" held by ITWG as a part of our NNFL development project. In this paper, outline and experiences of the JAEA investigation in the table top exercise are described and the lessons learned from the experiences were discussed. Brief current status of the NNFL development project at JAEA was also introduced in the present paper. The lessons from the experiences in the exercise will be effectively applied to the development of NNFL at JAEA.

Journal Articles

Present status and future plan of development on National Nuclear Forensics Library at JAEA

Kimura, Yoshiki; Shinohara, Nobuo; Funatake, Yoshio; Sato, Kaneaki; Toda, Nobufumi; Shinoda, Yoshiharu; Watahiki, Masaru; Kuno, Yusuke

Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-34-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2013/10

Japan Atomic Energy Agency (JAEA) has initiated R&D project on nuclear forensics technology such as analytical technologies towards the establishment of nuclear forensics capabilities in Japan. National Nuclear Forensics Library (NNFL) is one of the fundamental nuclear forensics capabilities and a prototype NNFL has been developed as one R&D topic of the project at JAEA. Main objective of a NNFL is to determine whether a seized nuclear or other radioactive material from nuclear security event (e.g. illicit trafficking) is originated from a country or not. Analytical data of the seized material are compared with the existing materials populated in a NNFL, and its attributions such as origin and history will be identified. This paper describes the current status and future plan on the development of prototype NNFL. The outline and the results of the participation in an international table top exercise on NNFL named "Galaxy Serpent" were also reported in the present paper.

Journal Articles

R&D status and future plan of nuclear forensics for analytical technology and national library at JAEA

Kimura, Yoshiki; Shinohara, Nobuo; Sato, Kaneaki; Toda, Nobufumi; Shinoda, Yoshiharu; Watahiki, Masaru; Kuno, Yusuke

Proceedings of INMM 54th Annual Meeting (CD-ROM), 7 Pages, 2013/07

Japan Atomic Energy Agency (JAEA) that possesses sufficient analytical capabilities to fulfil the mission of nuclear forensics technology development has started R&D project from JFY 2011. The R&D of the nuclear forensics technology at JAEA covers the development of analytical technology such as isotope and impurity measurements, morphology analysis, age determination technique, and proto-type of national nuclear forensics library. Each topic of the R&D has been promoted under the international cooperation with US-DOE. This paper will present the present status and brief results of the R&D project on nuclear forensics analytical technology and nuclear forensics library at JAEA. Some future plan of the R&D such as attribute identification of Japanese nuclear materials, data populating plan for existing nuclear materials data in JAEA fuel cycle facilities will be also introduced in the presentation.

Journal Articles

Complementary characterization of radioactivity produced by repetitive laser-driven proton beam using shot-to-shot proton spectral measurement and direct activation measurement

Ogura, Koichi; Shizuma, Toshiyuki; Hayakawa, Takehito; Yogo, Akifumi; Nishiuchi, Mamiko; Orimo, Satoshi; Sagisaka, Akito; Pirozhkov, A. S.; Mori, Michiaki; Kiriyama, Hiromitsu; et al.

Japanese Journal of Applied Physics, 51(4), p.048003_1 - 048003_2, 2012/04

 Times Cited Count:2 Percentile:10.01(Physics, Applied)

A proton beam driven by a repetitive high-intensity-laser is utilized to induce a $$^{7}$$Li(p,n)$$^{7}$$Be nuclear reaction. The total activity of $$^{7}$$Be are evaluated by two different methods. The activity obtained measuring the decay $$gamma$$-rays after 1912 shots at 1 Hz is 1.7$$pm$$0.2 Bq. This is in good agreement with 1.6$$pm$$0.3 Bq evaluated from the proton energy distribution measured using a time-of-flight detector and the nuclear reaction cross-sections. We conclude that the production of activity can be monitored in real time using the time-of-flight-detector placed inside a diverging proton beam coupled with a high-speed signal processing system.

Journal Articles

The Impact of advanced technologies on the efficiencies of safeguards and facility operations

Hoffheins, B.; Miyaji, Noriko; Asano, Takashi; Nagatani, Taketeru; Ishiyama, Koichi; Kimura, Takashi; Kodani, Yoshiki

Proceedings of INMM 52nd Annual Meeting (CD-ROM), 10 Pages, 2011/07

Following Japan's conclusion of the Additional Protocol and the IAEA's broader conclusion regarding the peaceful nature of Japan's nuclear activities, the Japan government and facility operators have worked with the IAEA to apply integrated safeguards to increase inspection efficiency and to ensure verification correctness and completeness. These safeguards approaches rely heavily on the implementation of advanced technologies such as unattended surveillance and non-destructive assay measurement, automated nuclear material accounting, solution monitoring and remote monitoring. These technologies have enabled random interim inspections; they have also reduced the level of effort required for nuclear material accounting and inspection activities. A more comprehensive understanding of the impact of advanced technologies on operation and inspection processes would be useful for developing methodologies to support better system design and evaluation of existing systems.

Journal Articles

Laser ceramic materials for subpicosecond solid-state lasers using Nd$$^{3+}$$ -doped mixed scandium garnets

Okada, Hajime; Tanaka, Momoko; Kiriyama, Hiromitsu; Nakai, Yoshiki*; Ochi, Yoshihiro; Sugiyama, Akira; Daido, Hiroyuki; Kimura, Toyoaki*; Yanagitani, Takagimi*; Yagi, Hideki*; et al.

Optics Letters, 35(18), p.3048 - 3050, 2010/09

 Times Cited Count:12 Percentile:54.33(Optics)

Journal Articles

Development of a high-contrast, high beam-quality, high-intensity laser

Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki*; Shimomura, Takuya; Sasao, Hajime*; Tanaka, Momoko; Ochi, Yoshihiro; Tanoue, Manabu*; Kondo, Shuji; Kanazawa, Shuhei; et al.

Reza Kenkyu, 38(9), p.669 - 675, 2010/09

This paper reviews the temporal contrast and spatial beam quality improvement techniques in a high intensity Ti:sapphire laser system that is based on chirped-pulse amplification (CPA). We describe a low gain optical parametric chirped-pulse amplification (OPCPA) preamplifier that uses high energy, clean pulse seeding and is shown to significantly improve the contrast to better than 10$$^{-10}$$-10$$^{-11}$$ relative to the peak of the main femtosecond pulse. We also report the use of a diffractive optical element for beam homogenization of a 100 J level Nd:glass green pump laser, achieving a flat-topped spatial profile with a filling factor near 80 %.

Journal Articles

High temporal and spatial quality petawatt-class Ti:sapphire chirped-pulse amplification laser system

Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki; Shimomura, Takuya; Sasao, Hajime; Tanoue, Manabu*; Kanazawa, Shuhei; Wakai, Daisuke*; Sasao, Fumitaka*; Okada, Hajime; et al.

Optics Letters, 35(10), p.1497 - 1499, 2010/05

 Times Cited Count:82 Percentile:95.96(Optics)

OPCPA (Optical parametric chirped-pulse amplification) operation with low gain by seeding with high energy, clean pulses is shown to significantly improve the contrast to better than $$10^{-10}$$-$$10^{-11}$$ in a high intensity Ti:sapphire laser system that is based on chirped pulse amplification. In addition to the high contrast broadband high energy output from the final amplifier is achieved with a flat-topped spatial profile of filling factor near 77%. This is the result of pump beam spatial profile homogenization with diffractive optical elements. Final pulse energies exceed 30-Joules indicating capability for reaching peak powers in excess of 500-TW.

Journal Articles

High spatiotemporal-quality petawatt-class laser system

Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki; Shimomura, Takuya; Sasao, Hajime; Tanaka, Momoko; Ochi, Yoshihiro; Tanoue, Manabu*; Okada, Hajime; Kondo, Shuji; et al.

Applied Optics, 49(11), p.2105 - 2115, 2010/04

 Times Cited Count:39 Percentile:86.23(Optics)

We have developed a femtosecond high intensity laser system, which combines both Ti:sapphire chirped-pulse amplification (CPA) and optical parametric chirped-pulse amplification (OPCPA) techniques, that produces more than 30-J broadband output energy, indicating the potential for achieving peak powers in excess of 500-TW. With a cleaned high-energy seeded OPCPA preamplifier as a front-end in the system, for the compressed pulse without pumping the final amplifier we found that the temporal contrast in this system exceeds 10$$^{10}$$ on the sub-nanosecond timescales, and is near 10$$^{12}$$ on the nanosecond timescale prior to the peak of the main femtosecond pulse. Using diffractive optical elements for beam homogenization of 100-J level high-energy Nd:glass green pump laser in a Ti:sapphire final amplifier, we have successfully generated broadband high-energy output with a near-perfect top-hat-like intensity distribution.

Journal Articles

Temporal contrast and spatial beam quality improvement techniques in a high intensity Ti:sapphire laser system

Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki; Shimomura, Takuya; Tanoue, Manabu*; Akutsu, Atsushi; Okada, Hajime; Motomura, Tomohiro*; Kondo, Shuji; Kanazawa, Shuhei; et al.

Reza Kenkyu, 37(6), p.425 - 430, 2009/06

This paper reviews the temporal contrast and spatial beam quality improvement techniques in a high intensity Ti:sapphire laser system that is based on chirped-pulse amplification (CPA). We describe an optical parametric chirped-pulse amplification (OPCPA) preamplifier that is seeded by a cleaned high-energy pulse. It demonstrates a background amplified spontaneous emission (ASE) level of 10$$^{-10}$$ relative to the peak main femtosecond pulse on the picosecond timescale. We also report a cryogenically-cooled Ti:sapphire final amplifier which generates focused peak intensity in excess of 10$$^{20}$$ W/cm$$^{2}$$ at a 10 Hz repetition rate.

Journal Articles

Proton-induced nuclear reactions using compact high-contrast high-intensity laser

Ogura, Koichi; Shizuma, Toshiyuki; Hayakawa, Takehito; Yogo, Akifumi; Nishiuchi, Mamiko; Orimo, Satoshi; Sagisaka, Akito; Pirozhkov, A. S.; Mori, Michiaki; Kiriyama, Hiromitsu; et al.

Applied Physics Express, 2(6), p.066001_1 - 066001_3, 2009/05

 Times Cited Count:14 Percentile:52.43(Physics, Applied)

Protons with energies up to 3.5 MeV have been generated by a 10 Hz compact laser with an intensity of about 10$$^{20}$$ W/cm$$^{2}$$, focused on a 7.5 mm thick polyimide target. These protons were used to induce a nuclear reaction of $$^{11}$$B(p,n)$$^{11}$$C. A total activity of 11.1 Bq was created after 60-shot laser irradiation. The possibility of thin layer activation (TLA) using a high-intensity ultra-short pulsed laser is discussed.

Journal Articles

Demonstration of highly efficient broadband amplification in a optical parametric chirped-pulse amplifier system

Okada, Hajime; Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki; Shimomura, Takuya*; Tanoue, Manabu*; Kondo, Shuji; Kanazawa, Shuhei; Daido, Hiroyuki; Kimura, Toyoaki*; et al.

Optical Review, 16(1), p.1 - 3, 2009/02

 Times Cited Count:8 Percentile:42.85(Optics)

Journal Articles

Generation of high-contrast and high-intensity laser pulses using an OPCPA preamplifier in a double CPA, Ti:sapphire laser system

Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki; Shimomura, Takuya; Tanoue, Manabu*; Akutsu, Atsushi; Okada, Hajime; Motomura, Tomohiro*; Kondo, Shuji; Kanazawa, Shuhei; et al.

Optics Communications, 282(4), p.625 - 628, 2009/02

 Times Cited Count:53 Percentile:91.22(Optics)

We demonstrate a high-contrast, high-intensity double chirped-pulse amplification (CPA) Ti:sapphire laser system using an optical parametric chirped-pulse (OPCPA) pre- amplifier. By injecting cleaned microjoule seed pulses into the OPCPA, a temporal contrast greater than $$10^{10}$$ within picosecond times before the main femtosecond pulse is demonstrated with an output pulse energy of 1.7 J and a pulse duration of 30 fs, corresponding to a peak power of 60 TW at a 10 Hz repetition rate. This system uses a cryogenically-cooled Ti:sapphire final amplifier and generates focused peak intensities in excess of $$10^{20}$$ W/$$cm^{2}$$.

Journal Articles

Development of integrated safeguards approach for JNC-1 site from the operator's viewpoint

Asano, Takashi; Fujiwara, Shigeo; Takahashi, Saburo; Nagatani, Taketeru; Fukuhara, Junichi; Kodani, Yoshiki; Kimura, Takashi; Miura, Yasushi

Proceedings of INMM 50th Annual Meeting (CD-ROM), 10 Pages, 2009/00

JAEA commenced to consider the integrated safeguards (IS) approach for JNC-1 site as the new concept of safeguards for further reduction of influence of facility operation by the safeguards activity. On the other hand, the board of governors of IAEA led the broader conclusion to Japan on June 2004 and safeguards implementation in Japan was transferred to the IS scheme in September 2004. IAEA aimed to improve efficiency of safeguards implementation for the plutonium handling facility by optimization of use of advanced safeguards systems and new safeguards regime without reduction of effectiveness of safeguards. The IS approach for JNC-1 site was developed and implemented on August 2008 after many discussions among IAEA, Japan Safeguards Office (JSGO) and JAEA. This paper shows contributions by JAEA to development of this approach from the operator's view point and influence to the operator by implementation of IS approach.

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