Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Kamada, Masaki*; Yoshida, Takuma*; Sugita, Tsukasa*; Okumura, Keisuke
Nihon Genshiryoku Gakkai-Shi ATOMO
, 66(2), p.83 - 86, 2024/02
no abstracts in English
Furutaka, Kazuyoshi; Ozu, Akira; Toh, Yosuke
Nuclear Engineering and Technology, 55(11), p.4002 - 4018, 2023/11
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Nagatani, Taketeru; Sagara, Hiroshi*; Kosuge, Yoshihiro*; Nomi, Takayoshi; Okumura, Keisuke
Journal of Nuclear Science and Technology, 60(4), p.460 - 472, 2023/04
Times Cited Count：1 Percentile：31.61(Nuclear Science & Technology)Koizumi, Mitsuo
Proceedings of 41st ESARDA Annual Meeting (Internet), p.260 - 267, 2019/05
Komeda, Masao; Ozu, Akira; Mori, Takamasa; Nakatsuka, Yoshiaki; Maeda, Makoto; Kureta, Masatoshi; Toh, Yosuke
Journal of Nuclear Science and Technology, 54(11), p.1233 - 1239, 2017/11
Times Cited Count：8 Percentile：61.27(Nuclear Science & Technology)The previous active neutron method cannot remove the influence of the multiplication effect of neutrons produced by second- and subsequent fission reactions, and it might overestimate the amount of nuclear material if an item contains large amounts. In this paper, we discussed the correction method for the neutron multiplication effect on the measured data in the fast neutron direct interrogation (FNDI) method, one of the active neutron methods, supposing that the neutron multiplication effect is caused mainly by third-generation neutrons from the second-fission reactions under the condition that the forth-generation neutrons are much fewer. This paper proposed a correction method for the neutron multiplication effect in the measured data. Moreover we have shown a possibility that this correction method gives rough estimates of the effective neutron multiplication factor and the subcriticality.
Bolind, A. M.*; Seya, Michio
JAEA-Review 2015-027, 233 Pages, 2015/12
JAEA-Review-2015-027.pdf:30.21MB
This report surveys the 14 advanced NDA techniques that were examined by the Spent Fuel NDA Project of the Next Generation Safeguards Initiative (NGSI) of the U.S. DOE-NNSA. It discusses and critique NDA techniques from a view point of obtaining higher accuracies. The report shows the main problem, large uncertainties in the assay results are caused primarily by using too few independent NDAs. In this report authors shows that at least three independent NDA techniques are required for obtaining better accuracies, since the physics of the NDA of SFAs is three dimensional.
Tsuchiya, Harufumi; Koizumi, Mitsuo; Kitatani, Fumito; Kureta, Masatoshi; Harada, Hideo; Seya, Michio; Heyse, J.*; Kopecky, S.*; Mondelaers, W.*; Paradela, C.*; et al.
Proceedings of 37th ESARDA Annual Meeting (Internet), p.846 - 851, 2015/08
One of non-destructive techniques using neutron resonance reaction is neutron resonance transmission analysis (NRTA). We are presently developing a new active neutron non-destructive method including NRTA in order to detect and quantify special nuclear materials (SNMs) in nuclear fuels containing MA. We aim at applying the technique to not only particle-like debris but also other materials in high radiation field. For this aim, we make use of fruitful knowledge of neutron resonance densitometry (NRD) that was developed for particle-like debris in melted fuel. NRTA detects and quantifies SNMs by means of analyzing a neutron transmission spectrum via a resonance shape analysis. In this presentation, we explain the basic of NRTA and its role in the active neutron technique. Then, with knowledge obtained in the development of NRD, we discuss items to be investigated for NRTA in our active neutron technique.
Seya, Michio; Kureta, Masatoshi; Soyama, Kazuhiko; Nakamura, Hironobu; Harada, Hideo; Hajima, Ryoichi
Proceedings of INMM 55th Annual Meeting (Internet), 10 Pages, 2014/07
JAEA has been implementing development programs of basic technologies of the following advanced NDA (non-destructive assay) of nuclear material (NM) for nuclear safeguards and security. (1) Alternative to 
He neutron detection using ZnS/B
O
ceramic scintillator, (2) NRD (neutron resonance densitometry) using NRTA (neutron resonance transmission analysis) and NRCA (neutron resonance capture analysis), (3) NRF (nuclear resonance fluorescence)-NDA using laser Compton scattered (LCS) 
-rays (intense mono-energetic -rays). The development program (1) is for NDA systems that use ZnS/BO ceramic scintillator as alternative neutron detector to He for coming shortage of its supply. The program (2) is for a NDA system of isotopic composition measurement (non-destructive mass spectroscopy) in targets such as particle-like melted fuel debris using NRTA and NRCA. The program (3) is for NDA systems using a specific NRF reaction of certain Pu/U isotope caused by mono-energetic LCS -ray with energy tuned to the specific excited state of the isotope. This paper introduces above three programs.
Rodriguez, D.
no journal, ,
With the improvement of technology, safeguards verifications must consider how to declare precise uncertainties, especially for new non-destructive assay techniques. For our delayed -ray spectroscopy technique, we are utilizing the inverse Monte Carlo analysis method. Systematic uncertainties are determined by analyzing full Monte Carlo spectra using the same analysis applied to the data. Preliminary results will be presented at this workshop.
-ray beamsSeya, Michio; Hajima, Ryoichi*; Hayakawa, Takehito*; Koizumi, Mitsuo
no journal, ,
The NRF-base NDA using monochromatic -rays would be used in nuclear security for secure detection of NM in thick shield and also for precise checking of interior structures of detected / suspicious objects. This NDA also would be used in nuclear safeguards for precise quantification of U/Pu isotopes in high radiation background, such as spent fuel assemblies / melted fuel debris in a canister. It is also useful for precise measurement of quantities of minor actinide isotopes in ADS (Accelerator Driven Sub-critical System; for transmutation of long-half-life minor actinides (MA)) fuels before and after irradiation in the ADS reactor core. In this presentation, we show actual NRF-NDA methods for these objects.
Riyana, E. S.; Sakamoto, Masahiro; Matsumura, Taichi; Terashima, Kenichi; Okumura, Keisuke
no journal, ,
Lan, Z.*; Wei, T.*; Hayakawa, Takehito*; Kamiyama, Takashi*; Sato, Hirotaka*; Arikawa, Yasunobu*; Mirfayzi, S. R.*; Koizumi, Mitsuo; Abe, Yuki*; Morace, A.*; et al.
no journal, ,
