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Status of the neutron time-of-flight single-crystal diffraction data-processing software STARGazer

矢野 直峰*; 山田 太郎*; 細谷 孝明*; 大原 高志; 田中 伊知朗*; 新村 信雄*; 日下 勝弘*

Acta Crystallographica Section D; Structural Biology (Internet), 74(11), p.1041 - 1052, 2018/11

STARGazer is a data processing software for neutron time-of-flight (TOF) single-crystal diffraction data collected by the IBARAKI Biological Crystal Diffractometer (iBIX) at the Japan Proton Accelerator Research Complex (J-PARC). This software creates hkl intensity data from three-dimensional (x, y, TOF) diffraction data. STARGazer is composed of both a data processing component and a data visualization component. This article describes the status of data processing software STARGazer and its data processing algorithms.


Magnetic-ordering propagation vectors of terbium hexaboride revisited

岩佐 和晃*; 伊賀 文俊*; 茂吉 武人*; 中尾 朗子*; 大原 高志

Journal of the Physical Society of Japan, 87(6), p.064705_1 - 064705_5, 2018/06

 パーセンタイル:100(Physics, Multidisciplinary)

The magnetic-ordered state of a single-crystal sample of TbB$$_{6}$$ has been studied with the high-precision neutron diffraction instrument SENJU installed at BL18 of the Materials and Life Science Facility in J-PARC. We observed new Bragg-reflection spots characterized by a propagation vector $$q_{rm M2}$$ = (1/4, 1/4, 0) below the N$'e$el temperature $$T_{rm N}$$ $$approx$$ 20 K, in addition to the $$q_{rm M1}$$ = (1/4, 1/4. 1/2) reported in the previous literatures. Because X-ray Thomson scattering measurements do not detect the $$q_{rm M2}$$ superlattice reflections at 13 K, $$q_{rm M2}$$ is a new magnetic-ordering propagation vector. The magnetic multi-q structure of TbB$$_{6}$$ is similar to that of CeB$$_{6}$$, whereas the ratio of the $$q_{rm M2}$$ amplitude to that of qM1 is smaller than in CeB$$_{6}$$. The combination of $$q_{rm M1}$$ and $$q_{rm M2}$$ is expected to assist the $$q_{rm L1}$$ = (1/2, 0, 0) lattice modulation.


Structure analysis and derivation of deformed electron density distribution of polydiacetylene giant single crystal by the combination of X-ray and neutron diffraction data

田代 孝二*; 日下 勝弘*; 細谷 孝明*; 大原 高志; 塙坂 真*; 吉澤 功徳*; 山元 博子*; 新村 信雄*; 田中 伊知朗*; 栗原 和男*; et al.

Macromolecules, 51(11), p.3911 - 3922, 2018/06

 パーセンタイル:100(Polymer Science)

The crystal structure of polydiacetylene giant single crystal has been analyzed on the basis of the two different methods of wide-angle neutron diffraction and X-ray diffraction. The X-ray result gives us the total electron density distribution. The neutron result tells the positions of atomic nuclei. As a result, the so-called bonded (or deformed) electron density, i.e., the electron density distribution due to the conjugation among the covalently bonded atoms along the polymer chain, can be estimated using the two information. The present report is the first example of the application of X-N method to the synthetic polymer species.


Verification of probabilistic fracture mechanics analysis code PASCAL

Li, Y.; 勝又 源七郎*; 眞崎 浩一*; 林 翔太郎*; 板橋 遊*; 永井 政貴*; 鈴木 雅秀*; 関東 康祐*

Proceedings of 25th International Conference on Nuclear Engineering (ICONE-25) (CD-ROM), 10 Pages, 2017/07



PASCAL信頼性向上ワーキンググループ活動報告; 平成27年度

Li, Y.; 林 翔太郎*; 板橋 遊*; 永井 政貴*; 関東 康祐*; 鈴木 雅秀*; 眞崎 浩一*

JAEA-Review 2017-005, 80 Pages, 2017/03




Application of profile fitting method to neutron time-of-flight protein single crystal diffraction data collected at the iBIX

矢野 直峰*; 山田 太郎*; 細谷 孝明*; 大原 高志; 田中 伊知朗*; 日下 勝弘*

Scientific Reports (Internet), 6, p.36628_1 - 36628_9, 2016/12

 被引用回数:4 パーセンタイル:44.93(Multidisciplinary Sciences)

We developed and employed a profile fitting method for the peak integration of neutron time-of-flight diffraction data collected by the IBARAKI Biological Crystal Diffractometer (iBIX) at the Japan Proton Accelerator Research Complex (J-PARC) for protein ribonuclease A and alpha-thrombin single crystals. Gaussian convolved with two back-to-back exponentials was selected as the most suitable fitting function, and a profile fitting algorithm for the integration method was developed. It was clearly demonstrated that the profile fitting method provides more accurate integrated intensities and model structures than the summation integration method at higher resolution shells.


Rapid measurement scheme for texture in cubic metallic materials using time-of-flight neutron diffraction at iMATERIA

小貫 祐介*; 星川 晃範*; 佐藤 成男*; 徐 平光; 石垣 徹*; 齋藤 洋一*; 轟 秀和*; 林 眞琴*

Journal of Applied Crystallography, 49(5), p.1579 - 1584, 2016/10


 被引用回数:7 パーセンタイル:26(Chemistry, Multidisciplinary)

The authors have developed texture measurement system on a time-of flight neutron diffractometer, iMATERIA (BL20, MLF/J-PARC, Japan). Quantitative Rietveld texture analysis for a duplex stainless steel was possible with one neutron beam exposure for several minutes without sample rotation. The minimum number of diffraction spectra required for the Rietveld texture analysis was experimentally determined as $$sim$$100. The suggested rapid measurement scheme used 132 spectra and determined volume fractions of texture components in both ferrite and austenite phases, quantitatively. This quantitative and rapid measurement scheme was established by utilizing the features of iMATERIA as a powder diffractometer, i.e. fairly high resolution in d-spacing and numerous detectors equipped in a wide range of scattering angle.


Development of a high power wideband polarizer for electron cyclotron current drive system in JT-60SA

三枝 幹雄*; 小山 岳*; 松原 史明*; 滝井 啓太*; 佐井 拓真*; 小林 貴之; 森山 伸一

Fusion Engineering and Design, 96-97, p.577 - 582, 2015/10

 被引用回数:1 パーセンタイル:81.41(Nuclear Science & Technology)



Inter-atomic force constants of BaF$$_{2}$$ by diffuse neutron scattering measurement

佐久間 隆*; Makhsun*; 酒井 竜太郎*; Xianglian*; 高橋 東之*; Basar, K.*; 井川 直樹; Danilkin, S. A.*

AIP Conference Proceedings 1656, p.020002_1 - 020002_4, 2015/04


10Kおよび295KにてBaF$$_{2}$$の中性子散漫散乱測定を実施し、295Kにおいて、振動する散漫散乱強度パターンが観察された。この散漫散乱パターンよりF-F間の相関効果を解析することができ、この相関効果とDebye-Waller因子から、295KにおけるBaF$$_{2}$$の最近接および第2近接原子間の力定数は各々4.40, 2.30eV/$AA$^{2}$$と求められた。



長壁 豊隆; 加藤 義博*; 本元 悟*; 桑原 慶太郎*

高圧力の科学と技術, 25(1), p.57 - 63, 2015/03

強相関電子系物質の圧力誘起相臨界領域で発現する新奇物性を、同一の高圧試料環境下において構造-磁性-伝導の相関の視点から研究するため、中性子回折用ハイブリッド式対向アンビル(HA)を用いて電気抵抗との同時測定を実現するための技術開発を行っており、現在、これに不可欠なガスケットの絶縁技術開発を中心に行っている。HAでは、中性子透過率を重視してアルミ合金(JIS A2017P)ガスケットを使用している。我々はこれに着目し、ガスケット表面に特殊な陽極酸化皮膜(ミタニライトト)を形成し、これを絶縁層として利用する方法を考案した。室温下でミタニライト皮膜付きガ スケットの加圧試験を行った結果、測定用リー ド線の断線やショートを起こさずに約6GPaの圧力発生に成功した。



徐 平光; 星川 晃範*; 林 真琴*; 秋田 貢一; 森井 幸生*; 石垣 徹*

日本材料学会第48回X線材料強度に関するシンポジウム講演論文集, p.7 - 9, 2014/07

Time-of-flight neutron diffraction may evidently accelerate the bulk texture measurement speed through the proper combination of multiple orientations distributed neutron detectors and the simultaneous multiple diffraction peak acquisition, and only few sample rotations are needed to be carried out. In addition to the omega-axis rotatable sample changer, a dedicated omega/chi two-axis rotatable goniometer is under urgent development. It is highly expected to play an important role to evaluate the bulk texture evolution of advanced materials during thermomechanical controlling process. Though the intrinsic difference in neutron diffraction spectra from different orientations (determined by each set of Bragg angle/azimuthal angle) evidently increases the technical difficulty in rapid texture analysis, the development of Materials Analysis Using Diffraction (MAUD, developed by Luca Lutterotti, et al.) and other relevant software/programs are bringing us much convenience. Moreover, in order to increase the accessibility to neutron diffraction bulk texture measurement instruments, the various cooperative researches and the mail-in services are being planned.


Synchrotron radiation-based M$"o$ssbauer spectra of $$^{174}$$Yb measured with internal conversion electrons

増田 亮*; 小林 康浩*; 北尾 真司*; 黒葛 真行*; 齋藤 真器名*; 依田 芳卓*; 三井 隆也; 伊賀 文俊*; 瀬戸 誠

Applied Physics Letters, 104(8), p.082411_1 - 082411_5, 2014/02

 被引用回数:9 パーセンタイル:45.24(Physics, Applied)



Development of a high power diplexer with short-slotted metal half mirrors for electron cyclotron current drive

三枝 幹雄*; 渥美 幸平*; 山口 智輝*; 小田 靖久; 坂本 慶司

Fusion Engineering and Design, 88(6-8), p.964 - 969, 2013/10

 被引用回数:2 パーセンタイル:72.96(Nuclear Science & Technology)

A neoclassical tearing mode (NTM) which is a resistive MHD instability driven by plasma pressure gradient in tokamak plasma is one of the key issues giving the upper limitation of plasma performance. It can be controlled by the local current drive in a magnetic island with electron cyclotron current drive (ECCD). Up to now, ECCD with pulse modulated gyrotron operation at duty of 50% have been done to drive current into only O-point. For improving a stabilizing efficiency of NTM, the fast directional switch had been developed. It makes the duty of ECCD system to 100% by switching beam direction for tracking the rotating O-point of a magnetic island of NTM. The new type diplexer as a fast switching device of high power millimeter wave was proposed and had been simulated with finite difference time domain (FDTD) method. A proposed diplexer consists of a ring corrugated circular waveguide, a pair of mitre-bends, and a pair of half mirrors. The low power switching operation of the mock-up diplexer with long-slotted metal half mirrors at the two frequency bands (137 GHz and 170 GHz) was veried. In this paper, the low power test results of the diplexer with new short-slotted metal half mirrors at a frequency band of 170 GHz is reported.


Numerical estimation of Ohmic loss of high power wideband diplexer for ECCD system

渥美 幸平*; 山口 智輝*; 長嶋 浩司*; 三枝 幹雄*; 福成 雅史*; 小田 靖久; 坂本 慶司

Plasma and Fusion Research (Internet), 8(Sp.1), p.2405077_1 - 2405077_4, 2013/06

A diplexer for high power millimeter wave has been developed as a fast switching device in ECCD system for improving a stabilizing efficiency of neoclassical tearing modes. The switching operation of diplexer was confirmed with the FDTD code developed in our laboratory and low power tests using a mock-up diplexer. The cooling design of half mirror will be a key issue of this development, so that the Ohmic loss of a miter bend and a half mirror of the ring resonator was estimated by the numerical simulations.


高速炉におけるガス巻込み現象の防止基準,1; 数値解析によるガス巻込み現象再現精度の検証

大島 宏之; 田中 伸厚*; 江口 譲*; 西村 元彦*; 功刀 資彰*; 内堀 昭寛; 伊藤 啓; 堺 公明

日本原子力学会和文論文誌, 11(4), p.316 - 328, 2012/12



Inter-atomic force constants of Ag$$_{2}$$O from diffuse neutron scattering measurement

和田 保*; 佐久間 隆*; 酒井 竜太郎*; 上原 寛之*; Xianglian*; 高橋 東之*; 神嶋 修*; 井川 直樹; Danilkin, S. A.*

Solid State Ionics, 225, p.18 - 21, 2012/10

 被引用回数:3 パーセンタイル:79.94(Chemistry, Physical)




鈴木 徹也*; 山中 啓輔*; 石野 まゆ子*; 篠原 康浩*; 長井 健介*; 津留 英司*; 徐 平光

鉄と鋼, 98(6), p.262 - 266, 2012/06

The work-hardening characteristics of anisotropic tensile deformations and the corresponding residual strain changes of pre-strained ferritic steels without and with ageing treatment were investigated by using angle dispersive neutron diffraction and electron back-scattering diffraction. The plastic deformation along the pre-strained direction leads to evident work-hardening at the beginning stage, showing discontinuous yielding behavior. Comparably, the plastic deformation perpendicular to the pre-strained direction shows continuously yielding. The tensile and compressive residual strains were found in the $$<$$200$$>$$ and $$<$$110$$>$$ grains along the pre-strained direction, respectively. It is also found that the difference in various oriented grains after strain ageing become more evident along the pre-strained direction but smaller perpendicular to the pre-strained direction, revealing a higher work hardening capability in the former case than in the latter case.


Inter-atomic force constants from correlation effects among thermal displacement of atoms in PbTe

Xianglian*; 佐久間 隆*; Mohapatra, S. R.*; 上原 寛之*; 高橋 東之*; 神嶋 修*; 井川 直樹

Molecular Simulation, 38(5), p.448 - 451, 2012/04

 パーセンタイル:100(Chemistry, Physical)

10K及び294KにおけるPbTeの中性子散漫散乱実験を行った結果、PbTeの散乱強度の振動項は原子の熱変位における相関効果によって説明できることを明らかにした。相関効果とDebye-Waller温度因子から計算した294Kにおける第1近接原子間の力定数は$$alpha$$ $$_{rm Pb-Te}$$=215eV/nm$$^{2}$$と、第2近接原子間のそれは、各々$$alpha$$ $$_{rm Pb-Pb}$$=108eV/nm$$^{2}$$及び$$alpha$$ $$_{rm Te-Te}$$=144eV/nm$$^{2}$$と求めることができた。


Hydrogen-bond network and pH sensitivity in transthyretin; Neutron crystal structure of human transthyretin

横山 武司*; 水口 峰之*; 鍋島 裕子*; 日下 勝弘*; 山田 太郎*; 細谷 孝明*; 大原 高志*; 栗原 和男; 友寄 克亮*; 田中 伊知朗*; et al.

Journal of Structural Biology, 177(2), p.283 - 290, 2012/02

 被引用回数:27 パーセンタイル:19.95(Biochemistry & Molecular Biology)

Transthyretin (TTR) is a tetrameric protein associated with human amyloidosis. In vitro, the formation of amyloid fibrils by TTR is known to be promoted by low pH. Here we show the neutron structure of TTR, focusing on the hydrogen bonds, protonation states and pH sensitivities. A large crystal was prepared at pD 7.4 for neutron protein crystallography. Neutron diffraction studies were conducted using the IBARAKI Biological Crystal Diffractometer with the time-of-flight method. The neutron structure solved at 2.0 ${AA}$ resolution revealed the protonation states of His88 and the detailed hydrogen-bond network depending on the protonation states of His88. This hydrogen-bond network is composed of Thr75, Trp79, His88, Ser112, Pro113, Thr118-B and four water molecules, and is involved in both monomer-monomer and dimer-dimer interactions, suggesting that the double protonation of His88 by acidification breaks the hydrogen-bond network and causes the destabilization of the TTR tetramer. In addition, the comparison with X-ray structure at pH 4.0 indicated that the protonation occurred to Asp74, His88 and Glu89 at pH 4.0. Our neutron model provides insights into the molecular stability of TTR related to the hydrogen-bond network, the pH sensitivity and the CH...O weak hydrogen bond.


Correlation effects among thermal displacements of atoms in KBr

佐久間 隆*; Xianglian*; 清水 識文*; Mohapatra, S. R.*; 磯崎 信宏*; 上原 寛之*; 高橋 東之*; Basar, K.*; 井川 直樹; 神嶋 修*

Solid State Ionics, 192(1), p.54 - 57, 2011/06

 被引用回数:9 パーセンタイル:52.18(Chemistry, Physical)

第3近接原子までの熱変位による相関効果を用いてKBr粉末の中性子散漫散乱を解析した。KBrの散漫散乱の振動項は、その他のイオン結晶と同様に第1,第2及び第3近接元素間の熱変位による相関効果によって説明でき、これら相関効果から、第1,第2及び第3近接元素間の力定数は各々0.83eV/$AA $^{2}$$, 0.50eV/$AA $^{2}$$, 0.41eV/$AA $^{2}$$と求めることができた。

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