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Go, J.*; Park, M.-H.*; Gao, S.*; 松宮 久*; Gong, W.; 辻 伸泰*
Journal of Alloys and Compounds, 1014, p.178749_1 - 178749_10, 2025/02
被引用回数：2 パーセンタイル：89.83(Chemistry, Physical)In Mg alloys, basal dislocation slip is the preferential slip system that is activated at room temperature, while non-basal slips are typically difficult to activate owing to their high critical resolved shear stress. Until now, minimal focus has been directed towards the influence of loading direction on slip behavior in pre-twinned AZ31 alloys. This study employed transmission electron microscopy to demonstrate that non-basal slips, specifically prismatic and pyramidal I slips, are activated under deformation conditions where de-twinning is difficult in a pre-twinned AZ31 Mg alloy. When the tensile loading direction is parallel to the precompression direction, de-twinning and basal slip are the primary deformation modes. Conversely, when the tensile loading direction is perpendicular to the precompression direction, where de-twinning is challenging to activate, both basal and non-basal slips, such as prismatic and pyramidal I slips, emerge as the primary deformation modes. These results indicate that the pre-twinned AZ31 Mg alloy cannot deform solely through basal slips, and the activation of either de-twinning or non-basal slips is necessary to satisfy the von Mises criterion. Our findings in this study demonstrate the impact of non-basal slip activity on macroscopic yield stress and overall deformation, hence enhancing the understanding of magnesium alloy deformation mechanisms.
小泉 光生; 伊藤 史哲*; Lee, J.; 弘中 浩太; 高橋 時音; 鈴木 敏*; 有川 安信*; 安部 勇輝*; Wei, T.*; 余語 覚文*; et al.
第45回日本核物質管理学会年次大会会議論文集(インターネット), 4 Pages, 2024/11
Neutron resonance transmission analysis (NRTA) is a non-destructive method applicable for measuring nuclear material using a time-of-flight (TOF) technique with a pulsed neutron source. To realize a high resolution compact NRTA system, use of a short-pulsed neutron source is essential. Laser-driven neutron sources (LDNSs) are well-suit for generating such neutron beams due to their short pulse width. The advances in laser technology will further reduce the system's size and improve practicality. In this study, we demonstrate the measurement of a neutron transmission TOF spectrum of a sample containing indium and silver using the LDNS of the Osaka University. The obtained spectrum was analyzed using the least-square nuclear-resonance fitting program, REFIT, showcasing for the first time the potential of an LDNS for nondestructive areal-density material characterization.
小泉 光生; 伊藤 史哲*; Lee, J.; 弘中 浩太; 高橋 時音; 鈴木 敏*; 有川 安信*; 安部 勇輝*; Lan, Z.*; Wei, T.*; et al.
Scientific Reports (Internet), 14, p.21916_1 - 21916_9, 2024/09
被引用回数：2 パーセンタイル：0.00(Multidisciplinary Sciences)Laser-driven neutron sources (LDNSs) can generate strong short-pulse neutron beams, which are valuable for scientific studies and engineering applications. Neutron resonance transmission analysis (NRTA) is a nondestructive technique used for determining the areal density of each nuclide in a material sample using pulsed thermal and epithermal neutrons. Herein, we report the first successful NRTA performed using an LDNS driven by the Laser for Fast Ignition Experiment at the Institute of Laser Engineering, Osaka University. The key challenge was achieving a well-resolved resonance transmission spectrum for material analysis using an LDNS with a limited number of laser shots in the presence of strong background noise. We addressed this by employing a time-gated 
Li-glass scintillation neutron detector to measure the transmission spectra, reducing the impact of electromagnetic noise and neutron and gamma-ray flashes. Output waveforms were recorded for each laser shot and analyzed offline using a counting method. This approach yielded a spectrum with distinct resonances, which were attributed to 
In and 
Ag, as confirmed through neutron transmission simulation. The spectrum was analyzed using the least-square nuclear-resonance fitting program, REFIT, demonstrating the possibility of using an LDNS for nondestructive areal-density material characterization.
Li, X.*; Zhu, R.*; Xin, J.*; Luo, M.*; Shang, S.-L.*; Liu, Z.-K.*; Yin, C.*; 舟越 賢一*; Dippenaar, R. J.*; 肥後 祐司*; et al.
CALPHAD; Computer Coupling of Phase Diagrams and Thermochemistry, 84, p.102641_1 - 102641_6, 2024/03
被引用回数：0 パーセンタイル：0.00(Thermodynamics)The phase transformations and pressure-volume dependencies of the Ti-45Al alloy with respect to pressure have been investigated by means of in-situ observation using multi anvil-type high-pressure devices and synchrotron radiation. Under hydrostatic compression from 0 to 10.1 GPa, about 2.3 vol. % of 
transforms continuously to 
2. Lattice parameters as well as volume fractions of these two phases have been determined as a function of pressure. Bulk moduli estimated using Birch-Murnaghan's equation of state are 148 GPa for the phase, 138 GPa for the 2 phase, and 149 GPa for their two-phase mixture of Ti-45Al alloy. First-principles have also applied to investigate bulk moduli of two single phases, and the deviation between calculations and measurements is discussed and attributed to mainly phase transformation. The presently study provides useful insights into thermodynamics of 2 and phases under high pressure.
余語 覚文*; Lan, Z.*; 有川 安信*; 安部 勇輝*; Mirfayzi, S. R.*; Wei, T.*; 森 隆人*; Golovin, D.*; 早川 岳人*; 岩田 夏弥*; et al.
Physical Review X, 13(1), p.011011_1 - 011011_12, 2023/01
被引用回数：26 パーセンタイル：96.42(Physics, Multidisciplinary)Neutrons are powerful tools for investigating the structure and properties of materials used in science and technology. Recently, laser-driven neutron sources (LDNS) have attracted the attention of different communities, from science to industry, in a variety of applications, including radiography, spectroscopy, security, and medicine. However, the laser-driven ion acceleration mechanism for neutron generation and for establishing the scaling law on the neutron yield is essential to improve the feasibility of LDNS. In this paper, we report the mechanism that accelerates ions with spectra suitable for neutron generation. We show that the neutron yield increases with the fourth power of the laser intensity, resulting in the neutron generation of 
in 
at a maximum, with 
Wcm
, 900 J, 1.5 ps lasers. By installing a "hand-size" moderator, which is specially designed for the LDNS, it is demonstrated that the efficient generation of epithermal (0.1-100 eV) neutrons enables the single-shot analysis of composite materials by neutron resonance transmission analysis (NRTA). We achieve the energy resolution of 2.3% for 5.19-eV neutrons 1.8 m downstream of the LDNS. This leads to the analysis of elements and isotopes within sub-
s times and allows for high-speed nondestructive inspection.
伊藤 史哲*; Lee, J.; 弘中 浩太; 小泉 光生; 余語 覚文*
Proceedings of 19th Annual Meeting of Particle Accelerator Society of Japan (インターネット), p.137 - 140, 2023/01
中性子共鳴透過分析(NRTA)は、パルス中性子を計量したい核物質に照射し、飛行時間(TOF)法を用いて測定核物質を非破壊測定する手法であるが、小型・高精度化には短パルスな小型中性子源が必要となる。近年発展著しいレーザー技術を用いたレー ザー駆動中性子源(LDNS)は、そのような中性子源として将来を期待されている。そこで我々はLDNSを用いたNRTAの技術開発を行い、実証実験を行った。その結果について報告する。
弘中 浩太; 伊藤 史哲*; Lee, J.; 小泉 光生; 高橋 時音; 鈴木 敏*; 余語 覚文*; 有川 安信*; 安部 勇輝*
第42回日本核物質管理学会年次大会会議論文集(インターネット), 4 Pages, 2021/11
中性子共鳴透過分析(NRTA)はパルス中性子源を用いてTOF測定を行うことで核物質を非破壊測定する手法であるが、小型・高精度化には短パルスな小型中性子源が必要となる。近年発展著しいレーザー技術を用いたレーザー駆動中性子源(LDNS)は、そのような中性子源として将来を期待されている。我々はLDNSを用いたNRTAの実現可能性を調べるため、大阪大学LFEXレーザーを用いて中性子TOF測定実験を行った。
Grazzi, F.*; Cialdai, C.*; Manetti, M.*; Massi, M.*; Morigi, M. P.*; Bettuzzi, M.*; Brancaccio, R.*; Albertin, F.*; 篠原 武尚; 甲斐 哲也; et al.
Rendiconti Lincei. Scienze Fisiche e Naturali, 32(3), p.463 - 477, 2021/09
被引用回数：6 パーセンタイル：29.35(Multidisciplinary Sciences)In this paper, we have studied an additively manufactured metallic component, intended for ultra-high vacuum application, the exit-snout of the MACHINA transportable proton accelerator beam-line. Metal additive manufacturing components can exhibit heterogeneous and anisotropic microstructures. Two non-destructive imaging techniques, X-ray computed tomography and Neutron Tomography, were employed to examine its microstructure. They unveiled the presence of porosity and channels, the size and composition of grains and intergranular precipitates, and the general behavior of the spatial distribution of the solidification lines. While X-ray computed tomography evidenced qualitative details about the surface roughness and internal defects, neutron tomography showed excellent ability in imaging the spatial density distribution within the component. The anisotropy of the density was attributed to the material building orientation during the 3D printing process. Density variations suggest the possibility of defect pathways, which could affect high vacuum performances. In addition, these results highlight the importance of considering building orientation in the design for additive manufacturing for UHV applications.
Mo/
Tc generator by (n, ) method, 3藤田 善貴; 関 美沙紀; 滑川 要二*; 西方 香緒里; 大伍 史久; 井手 広史; 土谷 邦彦; 佐野 忠史*; 藤原 靖幸*; 堀 順一*; et al.
KURNS Progress Report 2020, P. 136, 2021/08
高濃縮ウランの利用低減や核不拡散及び核セキュリティ、核分裂生成物の処理の観点から放射化法((n,)法)によるMo製造の研究開発が進められている。放射化法で生成されるMoの比放射能は極めて低いことから、娘核種であるTcを濃縮するためメチルエチルケトン(MEK)を用いた溶媒抽出法に着目した。照射ターゲットであるMoO
ペレットは、長時間照射すると還元されることが分かっている。本試験では、MoOが還元した際に酸化剤としてNaOClを使用する可能性を考慮し、MoOを溶解して得られたモリブデン酸ナトリウム水溶液中へのNaCl添加の有無がTc回収率に及ぼす影響を調べた。その結果、NaClはMEKへの
Tc抽出率を低下させる可能性が示唆された。
Park, J. S.*; 原田 正英; 長谷川 勝一; 春日井 好己; 明午 伸一郎; 酒井 健二; 鈴谷 賢太郎; 他55名*
Progress of Theoretical and Experimental Physics (Internet), 2021(6), p.063C01_1 - 063C01_12, 2021/06
被引用回数：1 パーセンタイル：11.79(Physics, Multidisciplinary)The Sterile Neutrino Search at the J-PARC Spallation Neutron Source (JSNS) experiment aims to search for sterile neutrino oscillations using a neutrino beam from muon decays at rest. The JSNS2 detector contains 17 tons of 0.1
gadolinium (Gd) loaded liquid scintillator (LS) as a neutrino target. Detector construction was completed in the spring of 2020. A slow control and monitoring system (SCMS) was implemented for reliable control and quick monitoring of the detector operational status and environmental conditions. It issues an alarm if any of the monitored parameters exceed a preset acceptable range. The SCMS monitors the high voltage of the photomultiplier tubes, the LS level in the detector, possible LS overflow and leakage, the temperature and air pressure in the detector, the humidity of the experimental hall, and the LS flow rate during filling and extraction. An initial 10 days of data-taking with a neutrino beam was done following a successful commissioning of the detector and SCMS in 2020 June. In this paper, we present a description of the assembly and installation of the SCMS and its performance.
decay of 
Te with a novel recoil-decay scintillation detectorXiao, Y.*; Go, S.*; Grzywacz, R.*; Orlandi, R.; Andreyev, A. N.; 浅井 雅人; Bentley, M. A.*; de Angelis, G.*; Gross, C. J.*; Hausladen, P.*; et al.
Physical Review C, 100(3), p.034315_1 - 034315_8, 2019/09
被引用回数：19 パーセンタイル：83.66(Physics, Nuclear)A search for super-allowed decay of N=Z nuclei Te and 
Xe was carried out using a novel recoil-decay scintillator detector at the tandem accelerator facility at Japan Atomic Energy Agency. Inorganic crystal scintillation material of YAP:Ce (Yttrium Aluminium Perovskite) coupled to position-sensitive photo-multiplier tube (PSPMT) was implemented for the first time in a radioactive decay experiment. Residues from the fusion-evaporation reaction 
Ni+
Fe
Xe
were separated by the JAEA Recoil Mass Separator (RMS) and implanted into the YAP:Ce crystal. decays of neutron-deficient tellurium isotopes were identified and proton-emission of I was observed. No conclusive evidence was found for the decay chain XeTe 
Sn within 3 days experiment. The cross section limit of 130 pb was obtained for production of two events of Xe, about an order of magnitude below the expectation based on earlier cross section measurements and HIVAP calculations.
伊能 康平*; Hernsdorf, A. W.*; 今野 祐多*; 幸塚 麻里子*; 柳川 克則*; 加藤 信吾*; 砂村 道成*; 広田 秋成*; 東郷 洋子*; 伊藤 一誠*; et al.
ISME Journal, 12(1), p.31 - 47, 2018/01
被引用回数：54 パーセンタイル：90.03(Ecology)岐阜県瑞浪市の超深地層研究所において、深度300メートルの地下水を地下坑道から採取し、地下微生物の生態系を調査した。その結果、花崗岩深部でマグマ由来のメタンに依存した微生物生態系が存在することを明らかにした。
Michel-Sendis, F.*; Gauld, I.*; Martinez, J. S.*; Alejano, C.*; Bossant, M.*; Boulanger, D.*; Cabellos, O.*; Chrapciak, V.*; Conde, J.*; Fast, I.*; et al.
Annals of Nuclear Energy, 110, p.779 - 788, 2017/12
被引用回数：79 パーセンタイル：99.22(Nuclear Science & Technology)SFCOMPO-2.0 is the new release of the NEA database of experimentally measured assays, i.e. isotopic concentrations from destructive radiochemical analyses of spent nuclear fuel samples, complemented with design information of the fuel assembly and fuel rod from which each sample was taken, as well as with relevant information on operating conditions and characteristics of the host reactors, which are necessary for the modelling and simulation of the isotopic evolution of the fuel during irradiation. SFCOMPO-2.0 has been developed and is maintained by the OECD Nuclear Energy Agency (NEA) under the guidance of the Expert Group on Assay Data of Spent Nuclear Fuel (EGADSNF) of the NEA Working Party on Nuclear Criticality Safety (WPNCS). In this paper, the new database is described. Applications of SFCOMPO-2.0 for computer code validation, integral nuclear data benchmarking, and uncertainty analysis in nuclear waste package analysis are briefly illustrated.
Sc and development of the 
subshell closureSteppenbeck, D.*; 武内 聡*; 青井 考*; Doornenbal, P.*; 松下 昌史*; Wang, H.*; 馬場 秀忠*; 郷 慎太郎*; Holt, J. D.*; Lee, J.*; et al.
Physical Review C, 96(6), p.064310_1 - 064310_10, 2017/12
被引用回数：20 パーセンタイル：80.57(Physics, Nuclear)理化学研究所のRIBFにて、中性子過剰核Scの励起状態を
Tiからの1陽子ノックアウト反応およびScの非弾性散乱によって生成し、そこからの脱励起線を観測することによってエネルギー準位を得た。その結果、第一励起状態が695keVと低く現れることがわかった。Caで知られているように中性子数34の閉殻構造が成り立っているとすると、第一励起状態は約2MeVと高く現れるはずであり、この結果はScでは中性子数34の新魔法数が消滅していることを示している。殻模型計算でもこの結果は得られ、中性子数34の殻ギャップが陽子数に応じて強く変化していることがその原因であることがわかった。
Am at neutron energies below fission threshold廣瀬 健太郎; 西尾 勝久; 牧井 宏之; 西中 一朗*; 太田 周也*; 永山 達郎*; 田村 信行*; 後藤 真一*; Andreyev, A. N.; Vermeulen, M. J.; et al.
Nuclear Instruments and Methods in Physics Research A, 856, p.133 - 138, 2017/06
被引用回数：5 パーセンタイル：39.65(Instruments & Instrumentation)Fission and capture reactions were simultaneously measured in the neutron-induced reactions of Am at J-PARC. Data were taken with the TOF method in 
= 0.1
20 eV. The fission events were observed by detecting prompt fission neutrons using liquid organic scintillators. The capture reaction was measured by detecting rays from the compound nuclei using the same detectors, where the prompt fission neutrons and capture rays were separated by a pulse shape analysis. The cross sections were obtained by normalizing the relative yields at the first resonance to evaluations or other experimental data. The ratio of the fission to capture cross sections at each resonance is compared with those from an evaluated nuclear data library and other experimental data. Some differences were found between the present values and the library/literature values at several resonances.
isobars from the 
island of inversionMorales, A. I.*; Benzoni, G.*; Watanabe, H.*; 角田 佑介*; Otsuka, T.*; 西村 俊二*; Browne, F.*; Daido, R.*; Doornenbal, P.*; Fang, Y.*; et al.
Physics Letters B, 765, p.328 - 333, 2017/02
被引用回数：38 パーセンタイル：92.42(Astronomy & Astrophysics)The level schemes of neutron-rich isotopes 
Co and Ni were populated in the 
decay of Fe and studied using -delayed -ray spectroscopy of the decay, at the RIBF in RIKEN, Japan. The experimental results were compared to state-of-the-art shell-model calculations, and indicate a dominance of prolate deformation in the low-lying states, coexisting with spherical states. The decay of the isobars is shown to progress in accordance to a new type of shell evolution, the so-called Type II, which involves many particle-hole excitations across energy gaps.
-phase in -based titanium aluminide intermetallicsLiss, K.-D.*; 舟越 賢一*; Dippenaar, R. J.*; 肥後 祐司*; 城 鮎美*; Reid, M.*; 鈴木 裕士; 菖蒲 敬久; 秋田 貢一
Metals, 6(7), p.165_1 - 165_22, 2016/07
被引用回数：20 パーセンタイル：63.68(Materials Science, Multidisciplinary)Ti-Al合金は、航空機エンジン材料として、軽量・耐熱タービンへの応用が期待されているが、塑性加工性の悪さを克服する必要がある。高圧鍛造プレスにおいては、10GPaの範囲で材料加工を可能にするが、それゆえに、極限環境における候補材料の状態図を評価する必要がある。本研究では、(
+)二相合金の一つであるTi-45Al-7.5Nb-0.25Cに対し、9.6GPaまでの圧力範囲、また1686Kまでの温度範囲で放射光X線回折によるその場実験を行った。室温では、圧力に対する体積変化は、両相に観察される明らかに高い体積弾性係数から、体積ひずみというよりはむしろ、相変態の影響と考えられる。結晶学的には、特に格子ひずみと原子配列について詳しく検討した。原子体積の増加にもかかわらず、この相変態を生じるのは興味深い。これは、の高い規則化エネルギーによるものである。高圧下において加熱すると、共析とソルバス遷移温度が上昇し、第三相の立方晶相が1350K以上で安定する。過去の研究において、相は塑性変形において高い延性があり、従来の鍛造過程において重要なものであることが明らかにされている。本研究では、作動環境下において有害とされる相の存在は確認されなかったが、従来の鍛造過程における理想的な加工条件幅を明らかにした。これらの結果より、新しい加工処理方法を提案することができた。
NiMorales, A. I.*; Benzoni, G.*; Watanabe, H.*; 西村 俊二*; Browne, F.*; Daido, R.*; Doornenbal, P.*; Fang, Y.*; Lorusso, G.*; Patel, Z.*; et al.
Physical Review C, 93(3), p.034328_1 - 034328_14, 2016/03
被引用回数：26 パーセンタイル：83.44(Physics, Nuclear)Low-lying excited states in Ni have been investigated at RIKEN by studying the decay of Co to Ni. Co was separated with BigRIPS, implanted into the WaS3ABi Silicon array, and the ray measured using the EURICA spectrometer. From the analysis, 60 new -ray transitions and 21 new levels in Ni were observed. The new experimental information is compared to shell-model calculations which include neutron excitation across the 
shell. The calculations reproduce rather well the observed states, implying that a clear understanding of these low-lying excitations has been achieved.
Mn; Probing collectivity up to N=44 in Fe isotopic chainBenzoni, G.*; Morales, A. I.*; Watanabe, H.*; 西村 俊二*; Coraggio, L.*; Itaco, N.*; Gargano, A.*; Browne, F.*; Daido, R.*; Doornenbal, P.*; et al.
Physics Letters B, 751, p.107 - 112, 2015/12
被引用回数：20 パーセンタイル：75.34(Astronomy & Astrophysics)The decays of Mn have been measured at the RIBF facility at RIKEN using the EURICA spectrometer combined with an active stopper consisting of a stack of Si detectors. Half-lives and -delayed neutron emission probabilities have been extracted for these decays, together with first experimental information on excited states populated in 
Fe. The data indicate a continuously increasing deformation for Fe isotopes up to A=70, and interpreted to be due to the interplay between quadrupole correlation of specific neutron orbitals and the monopole component of the proton-neutron interaction.
Polster, L.*; Schuemann, J.*; Rinaldi, I.*; Burigo, L.*; McNamara, A. L.*; Steward, R. D.*; Attili, A.*; Carlson, D. J.*; 佐藤 達彦; Ramos M
ndez, J.*; et al.
Physics in Medicine & Biology, 60(13), p.5053 - 5070, 2015/07
被引用回数：55 パーセンタイル：90.39(Engineering, Biomedical)TOPASとは、陽子線治療計画に幅広く利用されているソフトウェアである。本研究の目的は、TOPASに陽子の生物学的効果比(RBE)を計算する機能を追加することである。その目的のため、8つの生物物理モデルをTOPASに組み込んだ。それらモデルのうち4つは、RBEの指標となる物理学的なパラメータとしてLETを用い、残りの4つは、それぞれDNAダメージ数、平均z値, y値,飛跡構造を用いる。その中で、y値を指標としたモデルには、原子力機構が開発したマイクロドジメトリ機能が使われた。導入した8つのモデルの精度は、実験的に求めた陽子のRBEと比較することにより検証した。本研究は、陽子線治療を臨床診療へと近づけるための治療計画の最適化に重要な成果である。
