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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.
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.
spectrometry of molten core material from Fukushima Daiichi Nuclear Power Station unit 1, 2 and 3 cores for special nuclear material accountancy; Low-volatile FP and special nuclear material inventory analysis and fundamental characteristics of -rays from fuel debrisSagara, Hiroshi; Tomikawa, Hirofumi; Watahiki, Masaru; Kuno, Yusuke
Journal of Nuclear Science and Technology, 51(1), p.1 - 23, 2014/01
Times Cited Count：9 Percentile：57.19(Nuclear Science & Technology)Feasibility study of spectrometry of molten core material from Fukushima Daiichi Nuclear Power Station Unit 1, 2 and 3 cores for special nuclear material accountancy has been performed, focusing on the low-volatile fission product and heavy metal inventory analysis, and fundamental characteristics of -ray from fuel debris for passive measurement. The inventory ratio of low-volatile lanthanides, 
Eu and 
Ce, to special nuclear material were evaluated by whole core inventory in unit 1, 2 and 3 cores as reference value for homogenized molten fuel material, and also as a function of burnup for specific fuel debris, considering the sensitivity of enrichment, specific power, water void fraction, cooling time, calculation tool accuracy and release ratio. The same indices could be applied to unit 3, while the uncertainty of specific fuel debris of separated MOX fuel would be increased significantly. Source photon spectrum results showed the detectability of low-volatile high energy -rays emitted from Eu at least in 20 years after the accident, that from Ce/Pr in 10 years, and volatile 
Cs and 
Cs at least in 20 years with 99% or more release ratio. Mass attenuation coefficients of fuel debris was evaluated to be insensitive to its compositions in high energy region. Leakage photon ratio was evaluated with variety of parameters and significant impact was confirmed with certain size of fuel debris, its correlation was summarized with respect to the photopeak ratio of source Eu. Finally, preliminary study with hypothetical canister model of fuel debris based on TMI-2 experience, and future plan were introduced.
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.
Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.
JAEA-Technology 2013-021, 43 Pages, 2013/07
JAEA-Technology-2013-021.pdf:5.12MB
The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.
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.
Sagara, Hiroshi; Tomikawa, Hirofumi; Watahiki, Masaru; Kuno, Yusuke
Transactions of the American Nuclear Society, 107(1), p.803 - 804, 2012/11
Fission products(FPs) such as Eu, Ce, Ru have low release ratio in case of core melting event in severe accident to co-exist inside fuel debris in oxide or metallic phase, based on TMI-2 experience and source term experiments. Passive spectroscopy of Ce-144/Pr-144 was utilized in quantifying special nuclear material in fuel debris of TMI-2 historically, and the same methodology might be applied to high energy emitter, Eu-154 and Ru-106. Passive neutron measurement has been also utilized for quantifying nuclear material practically. Different from conventional spent fuel, however, fuel debris would be lost in information of irradiated profile, release ratio of volatile FPs, and so on. In the present paper, sensitivity analysis of low-volatile FPs and Cm-244 inventory in irradiated nuclear fuel in light water reactor was performed numerically to clarify the uncertainty of low-volatile FP and Cm inventory regarding fuel irradiation parameters and calculation methodology, and to derive applicable index to quantify nuclear material in fuel debris.
spectroscopy of low-volatile FPs for special nuclear material accountancy in molten core materialSagara, Hiroshi; Tomikawa, Hirofumi; Watahiki, Masaru; Kuno, Yusuke
Proceedings of INMM 53rd Annual Meeting (CD-ROM), 10 Pages, 2012/07
Reviewing the technologies applied to TMI-2, feasibility study of spectroscopy of low-volatile FPs for special nuclear material accountancy in molten core material or debris has been performed numerically, and the sensitivity of low-volatile FP nuclides on fuel contents, especially 
Pu, was studied with parameters of typical BWR fuel such as enrichment, burnup and neutron spectrum, heat density. Comparing TMI-2, a PWR reactor, broader neutron spectrum axial profile and irradiation cycle complexity of typical BWR fuel assemblies make more variance in the accumulation of daughter nuclides by neutron capture reactions. As results, Pu quantification, by burnup dependent Eu/Pu index has accuracy of 15-18% in 1-sigma level mainly affected by burnup uncertainty, and Pu quantification by Ce/Pu has accuracy of 20% as long as Ce released photon could be observed within 10 years, within the scope of inventory survey except for measurement uncertainty. Finally systematic image of fuel quantification by passive spectroscopy and, as future study, FPs quantification by passive measurement tests by mockup debris measurement with self-attenuation correction are introduced.
Imaizumi, Tomomi; Miyauchi, Masaru; Ito, Masayasu; Watahiki, Shunsuke; Nagata, Hiroshi; Hanakawa, Hiroki; Naka, Michihiro; Kawamata, Kazuo; Yamaura, Takayuki; Ide, Hiroshi; et al.
JAEA-Technology 2011-031, 123 Pages, 2012/01
JAEA-Technology-2011-031.pdf:16.08MB
The number of research reactors in the world is decreasing because of their aging. However, the planning to introduce the nuclear power plants is increasing in Asian countries. In these Asian countries, the key issue is the human resource development for operation and management of nuclear power plants after constructed them, and also the necessity of research reactor, which is used for lifetime extension of LWRs, progress of the science and technology, expansion of industry use, human resources training and so on, is increasing. From above backgrounds, the Neutron Irradiation and Testing Reactor Center began to discuss basic concept of a multipurpose low-power research reactor for education and training, etc. This design study is expected to contribute not only to design tool improvement and human resources development in the Neutron Irradiation and Testing Reactor Center but also to maintain and upgrade the technology on research reactors in nuclear power-related companies. This report treats the activities of the working group from July 2010 to June 2011 on the multipurpose low-power research reactor in the Neutron Irradiation and Testing Reactor Center and nuclear power-related companies.
Sagara, Hiroshi; Inoue, Naoko; Kawakubo, Yoko; Watahiki, Masaru
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-32-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2011/11
The Generation IV (GEN IV) Nuclear Energy Systems International Forum (GIF) Proliferation Resistance and Physical Protection Working Group (PRPP WG) was established in December 2002 in order to develop the PR&PP evaluation methodology for GEN IV nuclear energy systems. In the final report of "PR&PP Evaluation; Example Sodium Fast Reactor (ESFR) Full System Case Study," issued in October 2009, the demonstration study of PR&PP evaluation with the qualitative approach are summarized using ESFR with four scenario threats. The present paper reviews and analyzes some results of the ESFR case study, and identifies the challenges and direction for the PR&PP evaluation methodology with quantitative approach.
Sakurai, Satoshi; Watahiki, Masaru; Suzuki, Mitsutoshi; Kuno, Yusuke
Proceedings of INMM 52nd Annual Meeting (CD-ROM), 6 Pages, 2011/07
The national statement made by the Japan Government at 2010 Nuclear Security Summit at Washington D.C., U.S.A. was to develop its nuclear forensics detection and analysis technologies in a three-year period and to share them with the international community to contribute to strengthening the nuclear security regime. The Japan Atomic Energy Agency, JAEA, is the organization that possesses analytical capabilities with the potential to fulfill this nuclear forensics mission, since JAEA has been developing a wide range of analytical techniques for nuclear material samples from large size ones to trace level ones of environmental sampling. For this reason, JAEA starts R&D on nuclear forensics technology from JFY 2011. In the presentation reported will be JAEA's outline of R&D to establish nuclear forensics analytical capabilities including international cooperation. The summary of International Workshop on Nuclear Forensics on 5-6 October 2010 at Tokai, Japan will be also reported.
Ebisawa, Hiroyuki; Hanakawa, Hiroki; Asano, Norikazu; Kusunoki, Hidehiko; Yanai, Tomohiro; Sato, Shinichi; Miyauchi, Masaru; Oto, Tsutomu; Kimura, Tadashi; Kawamata, Takanori; et al.
JAEA-Technology 2009-030, 165 Pages, 2009/07
JAEA-Technology-2009-030.pdf:69.18MB
The condition of facilities and machinery used continuously were investigated before the renewal work of JMTR on FY 2007. The subjects of investigation were reactor building, primary cooling system tanks, secondary cooling system piping and tower, emergency generator and so on. As the result, it was confirmed that some facilities and machinery were necessary to repair and others were used continuously for long term by maintaining on the long-term maintenance plan. JMTR is planed to renew by the result of this investigation.
Okano, Masanori; Kuno, Takehiko; Nemoto, Hirokazu*; Yamada, Keiji; Watahiki, Masaru; Hiyama, Toshiaki
Proceedings of INMM 50th Annual Meeting (CD-ROM), 9 Pages, 2009/07
no abstracts in English
Surugaya, Naoki; Hiyama, Toshiaki; Watahiki, Masaru
Analytical Sciences, 24(6), p.739 - 744, 2008/06
Times Cited Count：1 Percentile：4.16(Chemistry, Analytical)A robotized sample preparation method for the determination of Pu, which is recovered by extraction reprocessing of spent nuclear fuel, by isotope dilution mass spectrometry is described. The automated system has a six-axis industrial robot, whose motility is very fast, accurate and flexible, installed in a glove box. The automation of the weighing and diluting steps enables operator-unattended sample pretreatment for highly precise analyses of Pu in aqueous solutions. By the developed system, Pu concentration in HNO
medium was successfully determined with a set of subsequent mass spectrometric measurements. The relative uncertainty in determining the concentration of Pu by isotope dilution mass spectrometry using this system for sample pretreatment was estimated to be less than 0.1 rel.% (
=2), which is equal to that expected of a talented analyst. The operation time required was the same as that by a skilled operator.
Surugaya, Naoki; Sato, Soichi; Jitsukata, Shu*; Watahiki, Masaru
Analytical Sciences, 24(4), p.527 - 530, 2008/04
Times Cited Count：2 Percentile：7.6(Chemistry, Analytical)Laser-induced photoacoustic spectroscopy was demonstrated in a quantitative analysis of Pu in nitric acid medium. Plutonium was quantitatively oxidized to Pu(VI) using Ce(IV). The photoacoustic measurement of Pu(VI) with maximum absorption at 830.5 nm was subsequently performed to determine the concentration. The photoacoustic signal was linearly proportional to the Pu(VI) ion concentration. The detection limit of Pu(VI) was estimated to be 0.5 
g/mL. By the proposed method, Pu concentration was successfully determined in a nuclear waste solution for use in nuclear materials management.
Surugaya, Naoki; Taguchi, Shigeo; Sato, Soichi; Watahiki, Masaru; Hiyama, Toshiaki
Analytical Sciences, 24(3), p.377 - 380, 2008/03
Times Cited Count：5 Percentile：17.2(Chemistry, Analytical)A simple and rapid spectrophotometric method has been developed for the determination of Pu in highly radioactive liquid waste. This method uses Nd(III) as an internal standard, which enables us to determine the concentration of Pu and to authenticate the whole analytical scheme as well. A Nd(III) standard was mixed with a sample solution and Pu was quantitatively oxidized to Pu(VI) with Ce(IV) in a nitric acid medium, having maximum absorbance at 830 nm. The spectrophotometric measurement of Pu(VI) was subsequently performed to determine the concentration compared with maximum absorbance of Nd(III) at 795nm. The proposed method was validated through comparison experiments with isotope dilution mass spectrometry and was successfully applied to the analysis for the nuclear waste management at spent nuclear fuel reprocessing plants.
Surugaya, Naoki; Taguchi, Shigeo; Kurosawa, Akira; Watahiki, Masaru
STI/PUB/1298 (CD-ROM), p.673 - 679, 2007/08
We have been analyzing nuclear materials at the Tokai pilot reprocessing plant, Japan, since 1977. To obtain reliable measurements for nuclear material such as uranium and plutonium, we have developed various kinds of measurement techniques and implemented effective ones for accountability and verification analyses in a nuclear material accountancy system. One of our role as a pilot plant has been successfully accomplished with the effort put into various analytical activities. Now, it is time to transfer the experience gained with our technology to the next large-scale commercial plant in Rokkasho. This paper presents our analytical methods and their results obtained using analytical techniques we have applied over recent years.
Taguchi, Shigeo; Surugaya, Naoki; Sato, Soichi; Kurosawa, Akira; Watahiki, Masaru; Hiyama, Toshiaki
JAEA-Technology 2006-040, 76 Pages, 2006/07
JAEA-Technology-2006-040.pdf:5.23MB
A spectrophotometric determination using neodymium as an internal standard has been developed for safeguards verification analysis of plutonium in highly radioactive liquid waste which is produced by the reprocessing of spent nuclear fuel. The method offers reduced sample preparation and analysis time compared to isotope dilution mass spectrometry. It uses neodymium as an internal standard, which allows for determining an index for the authentication of the analytical operation and the instrument conditions. The sample was mixed with a known amount of neodymium as an internal standard. Subsequently, plutonium was quantitatively oxidized to Pu(IV) by the addition of Ce(IV). Plutonium concentration was calculated from a relation between Nd(III)/Pu(VI) molar extinction coefficient ratio and their absorbance ratio. The expanded uncertainty of the repeated analysis of plutonium (n=5) was found to be 
15mgL
(confidence interval 95%) for a highly radioactive liquid waste sample (173mgL). The determination limit was calculated to be 6mgL (ten fold's the standard deviation). This method was validated through comparison experiments with isotope dilution mass spectrometry. The analytical results of plutonium in highly radioactive liquid waste using this method were agree well with values obtained using isotope dilution mass spectrometry. The proposed method was successfully applied for the independent on-site safeguards analysis at the Tokai Reprocessing Plant.nt on-site safeguards analysis at the Tokai Reprocessing Plant.
Taguchi, Shigeo; Surugaya, Naoki; Sato, Soichi; Kurosawa, Akira; Watahiki, Masaru; Hiyama, Toshiaki
JAEA-Technology 2006-041, 58 Pages, 2006/06
JAEA-Technology-2006-041.pdf:4.38MB
We have developed a method of spectrophotometric determination of plutonium (
10
M) in highly radioactive liquid waste for safeguards verification analysis. The method offers reduced sample preparation and analysis time compared to isotope dilution mass spectrometry. It uses neodymium as an internal standard, which allows for determining an index for the authentication of the analytical scheme and the inspection procedure. The relative expanded uncertainty of the repeated analysis (n = 5) was 8.9 % (coverage factor k = 2) for a highly radioactive liquid waste sample(173 mgL). The determination limit was calculated to be 6 mgL (ten fold's the standard deviation). This method was validated through comparison experiments with isotope dilution mass spectrometry. The analytical results of plutonium in highly radioactive liquid waste using this method were in good agreement with those obtained using isotope dilution mass spectrometry. It is to be noted that the neodymium standard is intended to be provided by the inspector so that an inspector can check the instrument conditions as well as the analytical scheme. The proposed method was successfully applied for the independent on-site safeguards analysis at the Tokai Reprocessing Plant.
Kitagawa, Osamu; Suzuki, Yoshimasa; Kurosawa, Akira; Watahiki, Masaru; Hiyama, Toshiaki
JAEA-Technology 2006-031, 29 Pages, 2006/03
JAEA-Technology-2006-031.pdf:2.92MB
Using the correlation between electric conductivity and acidity in solution, we have investigated an analytical method that is able to determine acidity in the nitric acid solution by measuring electric conductivity of sample diluted with distilled water, and correcting the electric conductivity for plutonium(Pu) and uranium(U) using multivariate analysis method. We obtained good results as follows, (1) Acidity in the nitric acid solutions containing Pu and U obtained by this method was good agreement, within 10%, compared with the acidity measured by potentiometric titration method. (2) For plutonium nitrate solution and plutonium-uranium mixed nitrate solution, the repeatability and reproducibility for the measurement of electric conductivity at 25.0
C were less than 0.52%, and 1.53% respectively. (3) Impurities such as americium and iron in the solutions did not influence to the measurement of electric conductivity, if total amounts of these impurities were less than 1% compared with those of Pu and U. From the results described above, electric conductivity measuring method has been applying to analysis of acidity in the nitric acid solutions containing Pu and U at high concentration handled in Plutonium Conversion Development Facility. Furthermore, this method can be expected for the application to analysis of acidity in nitric acid solutions containing Pu and U for reprocessing process.
