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The Performance of neutron diffractometers at long and short pulse spallation sources; Comparison between ESS and J-PARC

新井 正敏*; Andersen, K. H.*; Argyriou, D. N.*; Schweika, W.*; Zanini, L.*; Harjo, S.; 神山 崇*; 原田 正英

Journal of Neutron Research, 23(4), p.215 - 232, 2021/12

The general performance of diffractometers at the first long pulse spallation source ESS, is compared with their counterparts at J-PARC, a short pulse spallation source. The difference in the inherent pulse structure of these neutron sources presents opportunities for new concepts for instrumentation, where performance does not scale simply with source power. The article describes advantages and disadvantages of those diffractometers, adapting to the very different source characteristics. We find that the two sources offer comparable performance in flux and resolution when operating in high-resolution mode. ESS offers significant advantages in tunability and flexibility, notably in the ability to relax resolution in order to increase flux for a given experiment. On the other hand, J-PARC instruments perform very well in spite of the lower source power and allow better access to epithermal neutrons, of particular interest for PDF analysis of diffraction data.


Radioactivity and radionuclides in deciduous teeth formed before the Fukushima-Daiichi Nuclear Power Plant accident

高橋 温*; 千葉 美麗*; 棚原 朗*; 相田 潤*; 清水 良央*; 鈴木 敏彦*; 村上 忍*; 小荒井 一真; 小野 拓実*; 岡 壽崇; et al.

Scientific Reports (Internet), 11(1), p.10355_1 - 10355_11, 2021/05

 被引用回数:4 パーセンタイル:50.96(Multidisciplinary Sciences)

The Fukushima-Daiichi Nuclear Power Plant (FNPP) accident released substantial amounts of radionuclides into the environment. We collected 4,957 deciduous teeth, from children living in Fukushima and reference prefectures. Radioactivity was detected in most of the teeth examined and was attributed to the presence of natural radionuclides, including $$^{40}$$K and daughter nuclides in $$^{238}$$U and $$^{232}$$Th series. Additionally, artificial radionuclides, $$^{90}$$Sr and $$^{137}$$Cs, were detected in the teeth obtained from children from Fukushima and the reference prefectures. However, these radionuclides were not believed to have originated from the FNPP accident. Because the teeth examined in the present study were formed before the FNPP accident occurred, the aforementioned findings may serve as important control data for future studies regarding the radioactivity of teeth formed after the FNPP accident.


SENJU; A New time-of-flight single-crystal neutron diffractometer at J-PARC

大原 高志; 鬼柳 亮嗣; 及川 健一; 金子 耕士; 川崎 卓郎; 田村 格良; 中尾 朗子*; 花島 隆泰*; 宗像 孝司*; 茂吉 武人*; et al.

Journal of Applied Crystallography, 49(1), p.120 - 127, 2016/02

 被引用回数:44 パーセンタイル:95.7(Chemistry, Multidisciplinary)

SENJU, a time-of-flight Laue-type single-crystal neutron diffractometer, was developed at the Materials and Life Science Experimental Facility (MLF) of the Japan Accelerator Research Complex (J-PARC). Molecular structure analysis of a sub-millimeter taurine crystal and magnetic structure analysis of a MnF$$_{2}$$ crystal were performed to evaluate its performance.


Development status of the NMR system for the polarized $$^{3}$$He Neutron Spin Filter (NSF) in the MLF at J-PARC

酒井 健二; 奥 隆之; 林田 洋寿*; 吉良 弘*; 廣井 孝介; 猪野 隆*; 大山 研司*; 大河原 学*; 加倉井 和久; 篠原 武尚; et al.

JPS Conference Proceedings (Internet), 8, p.036015_1 - 036015_6, 2015/09

$$^{3}$$Heの中性子吸収断面積が強いスピン選択性を有することを利用した偏極$$^{3}$$Heフィルターは、ビーム調整が不要なため、ビームラインに設置すれば直ぐに使える簡便な中性子スピンフィルター(NSF)として利用できる。そのようなNSF実現のためには、NSFの$$^{3}$$He偏極度${it P}$を定常的にモニタするための核磁気共鳴(NMR)システムの開発が不可欠である。我々は断熱高速通過型(AFP)とパルス型NMRの特徴が相補的であることに着目して2つのシステムを併用した汎用性の高いNMRシステムを開発した。更に、J-PARCの中性子実験装置(BL10)での中性子透過率測定から得られた${it P}$で校正しながら、温度、パルスNMRの振動磁場の大きさや印可時間などの測定条件を変えて、AFPとパルスNMRの信号間の相関を測定した。例えば、パルスNMR測定に起因する減偏極率を0.1%以下になるまでパルスNMRの検出感度を小さくしても、2つのNMR信号間の線形性は確認できた。これらの結果から、我々は開発したNMRシステムが$$^{3}$$He偏極度モニタとして十分機能することを確認した。


Design and performance of high-pressure PLANET beamline at pulsed neutron source at J-PARC

服部 高典; 佐野 亜沙美; 有馬 寛*; 小松 一生*; 山田 明寛*; 稲村 泰弘; 中谷 健; 瀬戸 雄介*; 永井 隆哉*; 内海 渉; et al.

Nuclear Instruments and Methods in Physics Research A, 780, p.55 - 67, 2015/04

 被引用回数:68 パーセンタイル:99.15(Instruments & Instrumentation)



Pyrochemical treatment of spent nitride fuels for MA transmutation

林 博和; 佐藤 匠; 柴田 裕樹; 倉田 正輝; 岩井 孝; 荒井 康夫

Science China; Chemistry, 57(11), p.1427 - 1431, 2014/11

 被引用回数:5 パーセンタイル:6.09(Chemistry, Multidisciplinary)



Development of portable polarized $$^{3}$$He neutron spin filter and its application to magnetic field imaging at J-PARC

酒井 健二; 奥 隆之; 林田 洋寿; 吉良 弘*; 篠原 武尚; 及川 健一; 原田 正英; 加倉井 和久; 相澤 一也; 新井 正敏; et al.

Journal of Physics; Conference Series, 528, p.012016_1 - 012016_7, 2014/07

 被引用回数:2 パーセンタイル:70.65




鈴木 貞明; 柳生 純一; 正木 圭; 西山 友和; 中村 誠俊; 佐伯 寿; 星 亮; 澤井 弘明; 長谷川 浩一; 新井 貴; et al.

NIFS-MEMO-67, p.266 - 271, 2014/02



Sorption of Eu(III) on granite; EPMA, LA-ICP-MS, batch and modeling studies

福士 圭介*; 長谷川 優介*; 前田 耕志*; 青井 裕介*; 田村 明弘*; 荒井 章司*; 山本 祐平*; 青才 大介*; 水野 崇

Environmental Science & Technology, 47(22), p.12811 - 12818, 2013/11

 被引用回数:21 パーセンタイル:53.84(Engineering, Environmental)



High-speed classification of coherent X-ray diffraction Patterns on the K computer for high-resolution single biomolecule imaging

徳久 淳師*; 新井 淳也*; 城地 保昌*; 大野 善之*; 亀山 豊久*; 山本 啓二*; 畑中 正行*; Gerofi, B.*; 島田 明男*; 黒川 原佳*; et al.

Journal of Synchrotron Radiation, 20(6), p.899 - 904, 2013/11

 被引用回数:5 パーセンタイル:30.58(Instruments & Instrumentation)

Single-particle coherent X-ray diffraction imaging using X-ray free electron laser has potential to reveal a three-dimensional structure of a biological supra-molecule at sub-nano meter resolution. In order to realize this method, it is necessary to analyze as many as one million noisy X-ray diffraction patterns, each for an unknown random target orientation. To cope with the severe quantum noise we need to classify patterns according to their similarities and average similar patterns to improve the S/N ratio. We developed a high-speed scalable scheme to carry out classification on the K computer, a 10PFLOPS supercomputer at RIKEN Advanced Institute for Computational Science. It is designed to work on the real time basis with the experimental diffraction pattern collection at the X-ray free electron laser facility SACLA so that the result of classification can be feed-backed to optimize experimental parameters during the experiment. We report the present status of our effort of developing the system and also a result of application to a set of simulated diffraction patterns. We succeeded in classification of about one million diffraction patterns by running 255 separate one-hour jobs on 385-node mode.


Assembly study for JT-60SA tokamak

柴沼 清; 新井 貴; 長谷川 浩一; 星 亮; 神谷 宏治; 川島 寿人; 久保 博孝; 正木 圭; 佐伯 寿; 櫻井 真治; et al.

Fusion Engineering and Design, 88(6-8), p.705 - 710, 2013/10

 被引用回数:10 パーセンタイル:63.62(Nuclear Science & Technology)

The JT-60SA project is conducted under the BA satellite tokamak programme by EU and Japan, and the Japanese national programme. The project mission is to contribute to early realization of fusion energy by supporting ITER and by complementing ITER with resolving key physics and engineering issues for DEMO reactors. In this paper, the assembly of major tokamak components such as VV and TFC is mainly described. An assembly frame (with the dedicated cranes), which is located around the tokamak, is adopted to carry out the assembly of major tokamak components in the torus hall independently of the facility cranes for preparations such as pre-assembly in the assembly hall. The assembly frame also provides assembly tools and jigs to support temporarily the components as well as to adjust the components in final positions.


Decontamination of outdoor school swimming pools in Fukushima after the nuclear accident in March 2011

三枝 純; 操上 広志; 安田 良; 栗原 和男; 新井 栄揮; 黒木 良太; 松橋 信平; 小澤 隆志; 後藤 浩明; 高野 隆夫; et al.

Health Physics, 104(3), p.243 - 250, 2013/03

 被引用回数:3 パーセンタイル:27.41(Environmental Sciences)



Current status of a new polarized neutron reflectometer at the intense pulsed neutron source of the Materials and Life Science Experimental Facility (MLF) of J-PARC

武田 全康; 山崎 大; 曽山 和彦; 丸山 龍治; 林田 洋寿; 朝岡 秀人; 山崎 竜也; 久保田 正人; 相澤 一也; 新井 正敏; et al.

Chinese Journal of Physics, 50(2), p.161 - 170, 2012/04

The construction of a new polarized neutron reflectometer is now in progress at the Materials and Life Science Experimental Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC). MLF has the world's brightest pulsed neutron and muon sources (JSNS and MUSE). The user program of MLF has been already started in 2008, and now nine neutron and two muon spectrometers are in operation. Installation of the new reflectometer was expected to be completed in March 2011. However, the construction was interrupted by the massive earthquake hitting northeast Japan, including Tokai-mura where J-PARC is located. We expect to restart the user program of the new polarized neutron reflectometer at the beginning of next year (2012).


Current status of a time-of-flight single crystal neutron diffractometer SENJU at J-PARC

田村 格良; 及川 健一; 川崎 卓郎; 大原 高志; 金子 耕士; 鬼柳 亮嗣; 木村 宏之*; 高橋 美和子; 清谷 多美子*; 新井 正敏; et al.

Journal of Physics; Conference Series, 340, p.012040_1 - 012040_4, 2012/02

 被引用回数:10 パーセンタイル:94.05

SENJU is a state-of-the-art single crystal time-of-flight Laue diffractometer in Materials and Life Science Experimental Facility at Japan Proton Accelerator Research Complex (J-PARC). The diffractometer is designed for precise crystal and magnetic structure analyses under multiple extreme conditions, such as low temperature, high-pressure, high-magnetic field. A measurement using small sample less than 1.0 mm$$^{3}$$ will be also realized, which allows us to study wide variety of materials. SENJU is aimed at a poisoned decoupled moderator to obtain peak profiles of Bragg reflection, and intensity distributions of superlattice reflections and diffuse scatterings with good accuracy. At the beginning, the diffractometer will have 31 two-dimensional scintillator detectors to cover wide area of reciprocal lattice space by a single measurement. The instrument is currently under construction and is scheduled to start on-beam commissioning by the end of 2011.


U-Pu-Zr metal fuel fabrication for irradiation test at JOYO

中村 勤也*; 加藤 徹也*; 尾形 孝成*; 中島 邦久; 岩井 孝; 荒井 康夫

Proceedings of International Conference on Fast Reactors and Related Fuel Cycles (FR 2009) (CD-ROM), 12 Pages, 2012/00




菊地 啓修; 中村 勤也*; 岩井 孝; 中島 邦久; 荒井 康夫; 尾形 孝成*

日本原子力学会和文論文誌, 10(4), p.323 - 331, 2011/12




中村 勤也*; 尾形 孝成*; 菊地 啓修; 岩井 孝; 中島 邦久; 加藤 徹也*; 荒井 康夫; 魚住 浩一*; 土方 孝敏*; 小山 正史*; et al.

日本原子力学会和文論文誌, 10(4), p.245 - 256, 2011/12



Development of the pyrochemical process of spent nitride fuels for ADS; Its elemental technologies and process flow diagram

林 博和; 佐藤 匠; 柴田 裕樹; 岩井 孝; 西原 健司; 荒井 康夫

Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 6 Pages, 2011/12



Fabrication of U-Pu-Zr metallic fuel elements for irradiation test at Joyo

中村 勤也*; 尾形 孝成*; 菊地 啓修; 岩井 孝; 中島 邦久; 加藤 徹也*; 荒井 康夫; 小山 正史*; 板垣 亘; 曽我 知則; et al.

Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 8 Pages, 2011/12



Developments of in-situ SEOP polarized $$^{3}$$He neutron spin filter in Japan

吉良 弘; 坂口 佳史; 奥 隆之; 鈴木 淳市; 中村 充孝; 新井 正敏; 遠藤 康夫; Chang, L.-J.; 加倉井 和久; 有本 靖*; et al.

Journal of Physics; Conference Series, 294, p.012014_1 - 012014_5, 2011/06

 被引用回数:11 パーセンタイル:94.93

The pulsed neutron source of J-PARC has started to operate in 2008 in Japan. To study structure of magnetic material and soft matters, polarized neutron scattering techniques are very important and powerful tools. It is urgently necessary for us to develop neutron spin polarizers for pulsed neutron scattering experiments. So we began the development of the in-situ SEOP system aiming to use it as a NSF for incident beam polarization and polarization analysis. In previous test performed by Ino et al., the $$^{3}$$He polarization reached 50% and not saturated yet. After that experiment, we began improving the SEOP system by installing the high power laser diode, the prism beam splitter and optimizing the beam-transform optics. By using this improved system, we performed the polarization test at BL10 in J-PRC and achieved the $$^{3}$$He polarization of 73%. We keep improving this in-situ SEOP system aiming to use it s an incident neutron polarizer at J-PARC.

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