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社本 真一; Shin, K.*; 赤津 光洋*; 今井 正樹; 植田 大地*; 横尾 哲也*; 根本 祐一*; Hassan, A. M. A.*; Chang, L.-J.*; 家田 淳一; et al.
Applied Physics Letters, 127(13), p.132403_1 - 132403_5, 2025/09
被引用回数:0 パーセンタイル:0.00(Physics, Applied)FeTiO
is an ilumenite antiferromagnetic insulator with Fe
. Two-dimensional ferromagnetic honeycomb layers are antifferomagnetically stacked along the
-axis. The magnetic Bragg peak intensity is enhanced by ultrasound injection up to 300 % on the FeTiO
crystal at low temperatures. The large enhancement is attributed to the large spin-lattice coupling of Fe
in FeTiO
. The enhancement is lost above 35 K, suggesting that the energy splitting of the Fe
levels by the spin-orbit coupling is about 35 K. This finding opens a possibility for high efficiency acoustic spin pumping.
高橋 嘉夫*; 三浦 輝*; 山田 真也*; 関澤 央輝*; 新田 清文*; 橋本 直*; 蓬田 匠; 山口 瑛子; 岡田 信二*; 板井 啓明*; et al.
Journal of Hazardous Materials, 495, p.139031_1 - 139031_19, 2025/09
被引用回数:0 パーセンタイル:0.00(Engineering, Environmental)本発表では、2011年の福島第一原子力発電所事故で放出された放射性セシウム含有微粒子(CsMP)中のセシウムの化学状態を、高分解能X線吸収分光法(XANES)とマイクロX線蛍光(
-XRF)を用いて解析した。その結果、主にガラス中に溶解したセシウムと、内部空隙表面に濃縮したセシウムの2種が確認された。後者はもともと気体として存在し、溶けたガラスが冷えて固まる際に濃縮したと考えられる。これらの知見は、事故時のCsMP形成過程や今後の廃炉作業、安全評価に重要である。
Hu, F. F.*; Qin, T. Y.*; Su, Y. H.; He, L. H.*; Ao, N.*; Parker, J. D.*; 篠原 武尚; Wu, S. C.*
International Journal of Fatigue, 193, p.108826_1 - 108826_14, 2025/04
被引用回数:5 パーセンタイル:92.65(Engineering, Mechanical)The relaxation behaviors of residual stress and the influence on the fatigue resistance of S38C axles with induction hardening were investigated by using advanced Bragg-edge transmission imaging and neutron diffraction as well as XFEM-based numerical modeling. The Bragg-edge imaging results indicate that lattice parameters change as the crack develops, which then leads to a decrease of residual strain. In addition, it was observed from neutron diffraction results that all three residual stress components decrease with the crack growth. By contrast, the compressive residual stress in the axle surface was almost fully released when the crack propagated to the matrix material zone. Furthermore, residual stress relaxation was validated by the extended finite element method. These new insights confirm stress relaxation in railway S38C axles during crack propagation, which must be considered while carrying out the structural integrity assessment.
Hu, F.-F.*; Qin, T.-Y.*; Ao, N.*; 徐 平光; Su, Y. H.; Parker, J. D.*; 篠原 武尚; 菖蒲 敬久; Kang, G.-Z.*; Ren, M.-M.; et al.
Journal of Traffic and Transportation Engineering, 25(2), p.75 - 93, 2025/04
To accurately predict the remaining lifetime of surface-strengthened railway axles, a damage tolerance method considering three-dimensional (3D) residual stresses was proposed. By taking the induction-hardened carbon steel S38C axle as an example, two-dimensional (2D) distribution characterization of residual strain and 3D residual stress measurement were performed through comprehensive application of the neutron Bragg-edge transmission imaging and angle-dispersive neutron diffraction experiments. A numerical method was employed to implant the 3D residual stress into the axle model, and the remaining lifetime of the full-scale axle was studied by coupling the measured load spectrum, press-fit loads, and residual stresses. Experimental results shows that, both axial and hoop directions present a compressive residual strain gradient layer of about 3 mm, with a maximum compressive residual strain of up to -4500 
in the surface layer, yet a maximum tensile strain of up to 1000 
in the core. The maximum axial and hoop compressive stresses of the axle are about -500 MPa and -303 MPa respectively, while radial stresses overall fluctuate in the zero mean stress range. At depths beyond 4.5 mm from the surface layer, all three components are tensile stresses. The axle surface layer is subjected to compressive residual stresses, and crack propagation does not occur if the crack depth is less than 4.5 mm. Nevertheless, cracks propagate accelerates when the crack depth is greater than 4.5 mm. Different crack propagation depth thresholds lead to a larger calculated remaining lifetime for the residual stress-free condition than for the case where 3D residual stresses are taken into account. However, the axle remaining service mileage of the axle of 227000 Km under the most conservative conditions exceeds 3.5 non-destructive inspection (NDI) cycles, with a large safety margin. The experimental results can provide a scientific reference for the development and optimization of NDI cycles for surface-strengthened railway axles.
Sans-Planell, O.*; 篠原 武尚; Grazzi, F.*; Cantini, F.*; Su, Y. H.; 松本 吉弘*; Parker, J. D.*; Manke, I.*
Review of Scientific Instruments, 95(11), p.113702_1 - 113702_5, 2024/11
被引用回数:1 パーセンタイル:16.39(Instruments & Instrumentation)This study presents a significant development in the Energy-Resolved Neutron Imaging System RADEN, in the Japan Proton Accelerator Research Complex, Japan. Through a systematic study, the collimation power of the facility was reevaluated. To perform the calculation of the L/D factor of the beam, a state-of-the-art method has been used, along with a standard reference sample to measure the resolution of neutron images. To add robustness to the results, the study compares five different scintillators of different composition and thickness.
渡辺 賢一*; 須貝 優介*; 長谷川 創大*; 田中 清志朗*; 人見 啓太朗*; 野上 光博*; 篠原 武尚; Su, Y. H.; Parker, J. D.*; Kockelmann, W.*
Scientific Reports (Internet), 14, p.25224_1 - 25224_13, 2024/10
被引用回数:1 パーセンタイル:16.39(Multidisciplinary Sciences)Thallium bromide (TlBr) semiconductor detectors are being developed as promising candidates for high-detection-efficiency, high-energy-resolution, and room-temperature gamma-ray spectrometers. This study presents methods for evaluating TlBr crystal quality and carrier transport characteristics using neutron Bragg-dip imaging and the time-of-flight method for pulsed-laser-induced carriers, respectively. In this study, two samples obtained from both the upstream and downstream region in the crystal ingot were evaluated.
O
and CoFe
O
nanoparticles for removal of Sr
and Cs
from radioactively contaminated water伊藤 あずさ; Thirunavukkarasu, G.*; Hriljac, J. A.*
Frontiers in Environmental Chemistry (Internet), 5, p.1445482_1 - 1445482_19, 2024/09
SiO
コートしたFe
O
とCoFe
O
の超常磁性ナノ粒子を付加したゼオライトA、ゼオライトX及びNa、K型チャバサイトの開発を行い、それらの結晶構造に関わる分析及びイオン交換試験よって、吸着材としての特性を評価した。これら吸着材の合成は、次の3ステップで行った。まず、ソルボサーマル法でFe
O
とCoFe
O
のナノ粒子を合成し、次に、最初に合成したFe
O
とCoFe
O
のナノ粒子をゾルゲル法でSiO
コートした。最後に、ゼオライト合成過程でM
O
/SiO
をゼオライトに付加した。合成後、これら磁性ゼオライトをX線回析法、蛍光X線分析、ラマン分光法、試料振動型磁力計、走査電子顕微鏡及び透過型電子顕微鏡で分析した。それらの結果から、M
O
/SiO
粒子をゼオライトに付加した後も超常磁性を保っていたことが分かった。また、磁性ゼオライトAとゼオライトXのSr
吸着能評価、及び磁性Na、K型チャバザイトのCs
吸着能評価をイオン交換試験で行った。これらのイオン交換試験よって、M
O
/SiO
粒子がゼオライトの吸着サイトを塞ぐことなく、また、イオン交換試験後もM
O
/SiO
粒子がゼオライトから脱離していないことを確認した。
RhSi社本 真一; 山内 宏樹; 飯田 一樹*; 池内 和彦*; 金子 耕士; Chen, Y.-S.*; 矢野 真一郎*; Hsu, P.-T.*; Lee, M. K.*; Hall, A. E.*; et al.
Physical Review Research (Internet), 6(3), p.033303_1 - 033303_7, 2024/09
Mn
RhSiの磁気励起は少なくとも0.3から140meVに広がる。200Kでの非弾性散乱強度を積分することで、Mnサイト当たり約5
の磁気モーメントは、約5
であることがわかった。一方で、長距離磁気秩序の磁気モーメントは4Kでわずか2.61
であり、多くの部分が低温まで揺らいでいることがわかった。
Hu, F. F.*; Qin, T. Y.*; Ao, N.*; Su, Y. H.; Zhou, L.*; 徐 平光; Parker, J. D.*; 篠原 武尚; Chen, J.*; Wu, S. C.*
Engineering Fracture Mechanics, 306, p.110267_1 - 110267_18, 2024/08
被引用回数:4 パーセンタイル:49.39(Mechanics)Non-destructive and quantitative mapping of gradient residual strain distribution in surface-hardened railway S38C axles could provide a positive reference for determining service lifetime and maintenance strategy. To tackle this concern, time-of-flight neutron Bragg-edge transmission imaging was employed by real axle samples with and without impacted crater. A novel and simple procedure to formulate the residual strain field was also developed in this work, with the transmission batch code in Appendix A. By mapping the global two- dimensional residual strains, it can be verified that the residual strains into the axle are uniformly distributed in the hoop direction. Subsequently, it was revealed that the axial and hoop residual strains, respectively in the cylinder and the long strip samples prepared from a real S38C hollow axle, indicated a gradient evolution distribution with a depth of
8 mm, covering a range of -5500
1000 
for axial strains and -6500
1000 
for hoop strains. More importantly, the maximum compressive lattice strain of the cylinder sample was increased by 15.61%, and 22.35% at the impacting speeds of 100, and 125 m/s, respectively; and that of the long strip sample increased by 29.17%, and 43.70%, respectively. It can thus be concluded that lattice strains have redistributed around the impact crater, demonstrating the local alteration of the residual strain field. These new findings suggest the localized variation in residual strains should be taken into account while evaluating the service damage evolution of railway axles, especially those affected by high-speed impacts during operation.
Zhou, L.*; Zhang, H.*; Qin, T. Y.*; Hu, F. F.*; 徐 平光; Ao, N.*; Su, Y. H.; He, L. H.*; Li, X. H.*; Zhang, J. R.*; et al.
Metallurgical and Materials Transactions A, 55(7), p.2175 - 2185, 2024/07
被引用回数:4 パーセンタイル:51.23(Materials Science, Multidisciplinary)High-speed railway S38C axles undergo surface induction hardening for durability, but are susceptible to fatigue cracks from foreign object impact. The neutron diffraction method was employed to measure the residual strain in S38C axles, obtaining microscopic lattice distortion data, for the gradient layer at a depth of 8 mm under the surface. The results showed that after induction-hardening, the microscopic lattice distortion had a gradient distribution, decreasing with the distance from the surface. However, in the case of impacting speed of 600 km/m, the average microscopic lattice distortion increased with the distance from the surface, reaching a maximum augmentation of 55 pct. These findings indicate a strong experimental basis, and improve our understanding of the relationship between macroscopic residual stress and decision-making, in regard to operation and maintenance.
社本 真一; 赤津 光洋*; Chang, L.-J.*; 根本 祐一*; 家田 淳一
Applied Physics Letters, 124(11), p.112402_1 - 112402_5, 2024/03
被引用回数:2 パーセンタイル:29.63(Physics, Applied)Y
Fe
O
における超音波注入によるマグノン励起を非弾性中性子散乱によって研究した。その結果、縦波と横波の両方で超音波注入によりマグノン励起の非弾性中性子散乱強度が増強されることがわかった。

Linh, B. D.*; Corsi, A.*; Gillibert, A.*; Obertelli, A.*; Doornenbal, P.*; Barbieri, C.*; Duguet, T.*; G
mez-Ramos, M.*; Holt, J. D.*; Hu, B. S.*; et al.
Physical Review C, 109(3), p.034312_1 - 034312_15, 2024/03
被引用回数:3 パーセンタイル:64.72(Physics, Nuclear)理化学研究所RIビームファクトリーにて中性子過剰核
Arビームからの1中性子ノックアウト反応実験を行い、
Arのエネルギー準位および分光学的因子を導出した。特に、第一励起状態の
への分光学的因子が大きいことから、始状態の
Arの基底状態において中性子が
軌道を多く占めていることがわかった。これは、中性子数32がよい魔法数として知られる
Caとは異なった性質であり、カルシウムからアルゴンへと陽子が2個減ることで閉殻構造が大きく崩れることが明らかになった。
Soler, J. M.*; Jurado, D.*; Saaltink, M. W.*; Mart
nez, L.*; Hidalgo, J. J.*; Lanyon, G. W.*; Heule, M.*; 深津 勇太; Siitari-Kauppi, M.*; Havlov
, V.*; et al.
Applied Geochemistry, 162, p.105927_1 - 105927_12, 2024/02
被引用回数:2 パーセンタイル:36.73(Geochemistry & Geophysics)Within the framework of the GTS-LTD project (Grimsel Test Site, Long-Term Diffusion), a radionuclide transport experiment in unfractured granitic rock matrix was performed. Grimsel groundwater containing several radionuclide tracers (
H as HTO,
Cl
,
Na
,
Cs
,
Ba
) was continuously circulated through a packed-off borehole interval. The decrease in tracer concentrations in the solution was monitored for a period of 1266 days (March 05, 2014-August 22, 2017). Additionally, tracer breakthrough was monitored in an observation borehole at a distance of 18.6 cm. Core samples from new boreholes were collected immediately after the end of the experiment, allowing the measurement of tracer distributions in the rock. The observed patterns for the non-sorbing tracers (HTO,
Cl
) showed clear preferential transport directions, consistent with advective flow towards the gallery from which the boreholes were drilled. Final 3D modeling of the experiment can explain the measured concentrations in the boreholes and in the rock. Tracer transport for the conservative tracers (HTO,
Cl
) is affected by both diffusion and advection through the granitic rock matrix. Also, in situ accessible porosities deduced from the modeling (0.0014) are smaller than those measured in rock samples (about 0.009), pointing to unloading and destressing of the rock samples after drilling. At the spatial and temporal scales of the experiment, the effect of advection for the weakly sorbing
Na
is only minor, and it is practically negligible for the strongly sorbing tracers (
Cs
,
Ba
).
CoSi山内 宏樹; Sari, D. P.*; 安井 幸夫*; 坂倉 輝俊*; 木村 宏之*; 中尾 朗子*; 大原 高志; 本田 孝志*; 樹神 克明; 井川 直樹; et al.
Physical Review Research (Internet), 6(1), p.013144_1 - 013144_9, 2024/02
-Mn-type family alloys Mn
have three-dimensional antiferromagnetic (AFM) corner-shared triangular network. The antiferromagnet Mn
RhSi shows magnetic short-range order (SRO) over a wide temperature range of approximately 500 K above the N
el temperature
= 190 K. Mn
CoSi has the smallest lattice parameter and the lowest
in the family compounds. The quantum critical point (QCP) from AFM to the quantum paramagnetic state is expected near a cubic lattice parameter of 6.15
of Mn
CoSi is only 140 K, quantum critical behavior is observed in Mn
CoSi as the enhancement of the electronic specific heat coefficient
. We study how the magnetic SRO appears in Mn
CoSi by using neutron scattering,
SR, and physical property measurements. The experimental results show that the neutron scattering intensity of the magnetic SRO does not change much regardless of the suppressed magnetic moment in the long-range magnetic ordered state compared to those of Mn
RhSi. The initial asymmetry drop ratio of
SR above
becomes small, and the magnetic SRO temperature
is suppressed to 240 K. The results suggest that the Mn
CoSi is close to the QCP in the Mn
system.
渡辺 賢一*; 須貝 優介*; 長谷川 創大*; 人見 啓太朗*; 野上 光博*; 篠原 武尚; Su, Y. H.; Parker, J. D.*; Kockelmann, W.*
Sensors and Materials, 36(1), p.149 - 154, 2024/01
被引用回数:2 パーセンタイル:33.11(Instruments & Instrumentation)Thallium bromide (TlBr) semiconductor detectors are promising candidates for high-detection-efficiency, high-energy-resolution, and room-temperature gamma-ray spectrometers. In this study, we conducted neutron Bragg dip and electron backscatter diffraction (EBSD) imaging of TlBr crystals to measure the crystal orientation distribution. We confirmed that crystal grains were continuous over a certain distance along the solidification direction for samples fabricated with the current growth procedure.
Soler, J. M.*; Kek
l
inen, P.*; Pulkkanen, V.-M.*; Moreno, L.*; Iraola, A.*; Trinchero, P.*; Hokr, M.*; 
ha, J.*; Havlov
, V.*; Trpko
ov
, D.*; et al.
Nuclear Technology, 209(11), p.1765 - 1784, 2023/11
被引用回数:6 パーセンタイル:66.06(Nuclear Science & Technology)The REPRO-TDE test was performed at a depth of about 400 m in the ONKALO underground research facility in Finland. Synthetic groundwater containing radionuclide tracers (HTO, Cl-36, Na-22, Ba-133, Cs-134) was circulated for about four years in a packed-off interval of the injection borehole. Tracer activities were additionally monitored in two observation boreholes. The test was the subject of a modelling exercise by the SKB GWFTS Task Force. Eleven teams participated in the exercise, using different model concepts and approaches. Predictive model calculations were based on laboratory-based information concerning porosities, diffusion coefficients and sorption partition coefficients. After the experimental results were made available, the teams were able to revise their models to reproduce the observations. General conclusions from these back-analysis calculations include the need for reduced effective diffusion coefficients for Cl-36 compared to those applicable to HTO (anion exclusion), the need to implement weaker sorption for Na-22, compared to results from laboratory batch-sorption experiments, and the observation of large differences between the theoretical initial concentrations for the strongly-sorbing Ba-133 and Cs-134 and the first measured values a few hours after tracer injection. Different teams applied different concepts, concerning mainly the implementation of isotropic vs. anisotropic diffusion, or the possible existence of Borehole Disturbed Zones around the different boreholes. The role of microstructure was also addressed in two of the models.
Be ground-state molecular structure using
Be(
)
He triple differential reaction cross-section measurementsLi, P. J.*; Beaumel, D.*; Lee, J.*; Assi
, M.*; Chen, S.*; Franchoo, S.*; Gibelin, J.*; Hammache, F.*; Harada, T.*; 延与 佳子*; et al.
Physical Review Letters, 131(21), p.212501_1 - 212501_7, 2023/11
被引用回数:30 パーセンタイル:93.79(Physics, Multidisciplinary)
Beのクラスター構造を(
)反応を用いて調査した。三重微分断面積が実験的に測定され、Tohsaki-Horiuchi-Schuck-R
pke波動関数の方法や反対称化分子動力学を用いた歪曲波インパルス近似計算と比較した。実験データと理論計算の顕著な一致が確認され、
Beの比較的コンパクトな分子状態を確認した。
O近藤 洋介*; Achouri, N. L.*; Al Falou, H.*; Atar, L.*; Aumann, T.*; 馬場 秀忠*; Boretzky, K.*; Caesar, C.*; Calvet, D.*; Chae, H.*; et al.
Nature, 620(7976), p.965 - 970, 2023/08
被引用回数:40 パーセンタイル:94.82(Multidisciplinary Sciences)非常に中性子が過剰な原子核
Oは、陽子、中性子ともに魔法数であることから古くからその性質に興味が持たれていたが、酸素の最後の束縛核
Oよりも中性子が4個も多いため、これまで観測されてこなかった。この論文では、理化学研究所RIBFにて
Fからの1陽子ノックアウト反応によって
Oを生成し、そこから放出される中性子を測定することによって初めてその観測に成功した。核構造の観点からは、
Oでは二重閉殻が保たれているか興味が持たれていたが、実験で得られた分光学的因子が殻模型計算で予言されて程度の大きいことから、閉殻構造をもたない可能性が高いことがわかった。
Ca cast doubt on a doubly magic
CaChen, S.*; Browne, F.*; Doornenbal, P.*; Lee, J.*; Obertelli, A.*; 角田 佑介*; 大塚 孝治*; 茶園 亮樹*; Hagen, G.*; Holt, J. D.*; et al.
Physics Letters B, 843, p.138025_1 - 138025_7, 2023/08
被引用回数:10 パーセンタイル:84.44(Astronomy & Astrophysics)
Scからの1陽子ノックアウト反応を用いて、
Caと
Caのガンマ崩壊を観測した。
Caでは1456(12)keVの
線遷移が、
Caでは1115(34)keVの遷移が観測された。どちらの遷移も暫定的に
と割り当てられた。有効核子間相互作用をわずかに修正した広い模型空間での殻模型計算では、
準位エネルギー、2中性子分離エネルギー、反応断面積が実験とよく一致し、N=34閉殻の上に新しい殻が形成されていることを裏付けた。その構成要素である
と
軌道はほぼ縮退しており、これは
Caが二重魔法核である可能性を排除し、Ca同位体のドリップラインを
Caあるいはそれ以上にまで広げる可能性がある。
Ne at the transition into the island of inversion; Detailed structure study of
NeWang, H.*; 安田 昌弘*; 近藤 洋介*; 中村 隆司*; Tostevin, J. A.*; 緒方 一介*; 大塚 孝治*; Poves, A.*; 清水 則孝*; 吉田 数貴; et al.
Physics Letters B, 843, p.138038_1 - 138038_9, 2023/08
被引用回数:6 パーセンタイル:70.06(Astronomy & Astrophysics)
Neからの1中性子除去反応を用いて、
Neの詳細な
線分光を行った。平行運動量分布の解析に基づき、
Neの準位構造とスピンパリティを決定し、初めて負のパリティ状態を同定した。測定された断面積と運動量分布から、N=20とN=28のシェルギャップの消失の証拠となる有意なintruder p-wave強度が明らかになった。束縛状態については、弱いf-waveの可能性のある強度が観測された。いくつかの有効相互作用を用いた大規模殻模型計算では、実験的に観測された大きなp-wave強度と小さなf-wave強度は再現されず、Ne同位体に沿った反転の島への遷移の完全な理論的記述への挑戦が続いていることを示している。