Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
FmOrlandi, R.; 浅井 雅人; 牧井 宏之; 西尾 勝久; 廣瀬 健太郎; 塚田 和明; 佐藤 哲也; 伊藤 由太; 洲嵜 ふみ; 永目 諭一郎*; et al.
Physical Review Letters, 137(8), p.082501_1 - 082501_6, 2026/08
被引用回数:1 パーセンタイル:73.88(Physics, Multidisciplinary)The ground-state rotational band of
Fm (
= 100,
= 152) was investigated using two different experimental setups at the JAEA Tandem Accelerator Laboratory. The first five
-ray transitions of the ground-state rotational band were observed for the first time. The new data revealed that
Fm possesses the lowest first excited
state energy, 41.88(16) keV, and the largest kinematic moment of inertia compared to neighboring isotopes in this region. These unique properties provide strong evidence for deformed shell gaps at
= 100 and
= 152, revealing that
Fm is a deformed doubly magic nucleus.
Qin, T. Y.*; Hu, F. F.*; 徐 平光; Zhang, R.*; Su, Y. H.; Ao, N.*; Li, Z. W.*; 篠原 武尚; 菖蒲 敬久; Wu, S. C.*
International Journal of Fatigue, 202, p.109233_1 - 109233_16, 2026/01
被引用回数:7 パーセンタイル:82.70(Engineering, Mechanical)The surface induction-hardened S38C medium carbon steel shows a good balance of strength and toughness, but complicates the evaluation of fatigue resistance, mainly because of gradient residual stress (RS) and grains. An integrated fatigue resistance assessment (AIFA) framework was proposed to consider the residual stress relief under stochastic loads. To this end, quasi-in situ neutron diffraction and Bragg-edge imaging were combined to probe the evolution of residual stress during crack propagation. Firstly, a rigid-flexible coupled vehicle dynamics model was adopted to obtain the time-domain variable amplitude loading spectrum. Then, Fortran subroutines were developed to assign these data into full-scale S38C axle model, and the remaining life was predicted using the damage tolerance approach. The results demonstrate that crack propagation would accelerate when residual stress is considered in the case of the crack depth exceeding 3.0 mm. It is, for the first time, found that 15 mm- and 5 mm-thickness fan-shaped specimens can retain the axial and hoop residual strain in terms of diffraction angle variation, respectively, for full-scale structural S38C steel axles. In the absence of RS, the remaining life of the axle decreases sharply from 624,800 to 51,300 km as the crack depth increases from 3.0 to 16 mm. Compared with the standard method under constant amplitude loading without residual stress relief, the present AIFA method provides the more accurate but conservative fatigue life prediction.
-wave
baryonsSu, N.*; Chen, H.-X.*; Gubler, P.; 保坂 淳
Physical Review D, 113(1), p.016005_1 - 016005_7, 2026/01
被引用回数:1 パーセンタイル:67.85(Astronomy & Astrophysics)Using the QCD sum rule method, we investigate the mass splitting for the spin-orbit partner states of the
baryon assuming that it is a
-wave excitation with
. This study is an extension of a previous work, in which the masses of these states were estimated with uncertainties too large to extract the reliable mass splitting. In the present study, by directly formulating a sum rule for the mass splitting, we obtain an improved prediction,
MeV. This result provides a more quantitative insight into the spectrum of
-wave
baryons and serves as a useful reference for future experiments.
from QCD sum rulesSu, N.*; Chen, H.-X.*; Gubler, P.; 保坂 淳
Proceedings of Science (Internet), 500, p.076_1 - 076_6, 2026/01
We investigate the recently observed
baryon using QCD sum rules. By constructing P-wave
baryon currents and performing spin projection and parity projection, we obtain the masses of the
and
states as
GeV and
GeV, in good agreement with experiment. This suggests that
is likely to be a negative parity P-wave excited state, though its spin remains undetermined and requires further study of its decay properties.
Malatesta, L. C.*; 末岡 茂; Wei
, N.-M.*; Gailleton, B.*; 塚本 すみ子*; 石村 大輔*; 高橋 直也*; 西村 卓也*; 片岡 香子*; 小松 哲也; et al.
Geophysical Research Letters, 52(24), p.e2025GL116602_1 - e2025GL116602_10, 2025/12
被引用回数:1 パーセンタイル:0.00(Geosciences, Multidisciplinary)The eastern margin of the Sea of Japan is a zone of great seismic and tsunami hazard due to multiple offshore and nearshore reverse faults as shown by the 2024 Mw7.5 Noto Peninsula Earthquake. Here we compare coseismic deformation of the 2024 Noto Peninsula Earthquake with 4,767 individual marine terraces attributed to 16 successive sea-level stages over the last Myr. This reveals that the earthquake faults started slipping between 326 and 238 ka. The emerged landscape is still adjusting to it while nearshore underwater scarps mark the active faults. Applied to nearby Sado Island, these observations reveal the likely location of an active fault that drives its fast deformation. Active faults defining the edge of uplifting land are likely found in the near shore domain, drowned by the current sea-level high stand.
板山 由依*; Davaasuren, D.*; 落合 伸也*; 南 雅代*; 益木 悠馬*; 由水 千景*; 内田 真緒; 丹羽 正和; 陀安 一郎*; 長尾 誠也*; et al.
Catena, 258, p.109297_1 - 109297_11, 2025/10
被引用回数:1 パーセンタイル:23.95(Geosciences, Multidisciplinary)Eastern Mongolia Plateau is situated at a northern limit of the current East Asian summer monsoon facing the Westerlies and is important area for understanding of the paleo environmental changes. This study investigated geochemical and physical properties of a 49 cm length sediment core, retrieved from the deepest part in Lake Buir, eastern Mongolia, to reveal the sedimentary records of the recent past climate changes.
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:6 パーセンタイル:77.48(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:8 パーセンタイル:82.70(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.
from QCD sum rulesSu, N.*; Chen, H.-X.*; Gubler, P.; 保坂 淳
Nuclear and Particle Physics Proceedings, 347, p.2 - 5, 2024/12
We investigate the recently observed
baryon using QCD sum rules. By constructing P-wave
baryon currents and performing spin projection and parity projection, we obtain the masses of the
and
states as
GeV and
GeV, in good agreement with experiment. This suggests that
is likely to be a negative parity P-wave excited state, though its spin remains undetermined and requires further study of its decay properties.
7/2 low-spin states in
Fr populated in the electron capture of the 1/2
ground state of
RaClisu, C.*; Andreyev, A. N.; Nita, C. R.*; 他42名*
Physical Review C, 110(6), p.064315_1 - 064315_15, 2024/12
被引用回数:2 パーセンタイル:37.47(Physics, Nuclear)A level scheme of
Fr, following the EC/
decay of its parent, was constructed at CERN's ISOLDE Decay Station. The
decay strength suggests direct population of low-spin (
=7/2) excited states. Analysis of
-single and
coincidences identified new
-ray transitions and states up to
3.6 MeV. Spins and parities of these levels, beyond the known (7/2
) state, were assigned based on
=126 isotone systematics and compared to shell-model calculations. A new isomer with a half-life of 26(3)~ns was also found.
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:5 パーセンタイル:40.95(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.
Qin, T. Y.*; Hu, F. F.*; 徐 平光; Zhang, H.*; Zhou, L.*; Ao, N.*; Su, Y. H.; 菖蒲 敬久; Wu, S. C.*
International Journal of Fatigue, 185, p.108336_1 - 108336_13, 2024/08
被引用回数:22 パーセンタイル:89.47(Engineering, Mechanical)Gradient distribution of triaxial residual stresses to a depth of several millimeters is retained in middle carbon steel S38C axles after high-frequency induction hardening, which has become a critical concern for fatigue structural integrity. To address this, the axial, hoop, and radial gradient residual strains inside the axles were measured for the first time by advanced neutron diffraction. The SIGINI Fortran subroutine was then adopted to reconstruct the global initial residual stress field from the measured data. Experimental and simulation results show that residual stresses of about -520 MPa (axial), -710 MPa (hoop), and -40 MPa (radial) residual stress were retained below the axle surface. Subsequently, the fatigue crack propagation behavior of S38C axles was numerically investigated in the framework of fracture mechanics. The calculated results clearly show that the compressive residual stresses at a depth of 0?3 mm from the axle surface lead to a low crack growth driving force, and that fatigue cracks do not propagate as long as the crack depth is less than 3.7 mm for hollow S38C axles. These results further indicate that the maximum defect size allowed in routine inspections is acceptable from a safety and economic point of view. Accurate measurement and characterization of the global gradient residual stress field through experiments and simulations can provide an important reference for optimizing the mileage intervals of nondestructive testing (NDT) of surface defects in these surface-strengthened railway axles.
from QCD sum rulesSu, N.*; Chen, H.-X.*; Gubler, P.; 保坂 淳
Physical Review D, 110(3), p.034007_1 - 034007_9, 2024/08
被引用回数:9 パーセンタイル:70.13(Astronomy & Astrophysics)We study the recently observed
baryon in quantum chromodynamics (QCD) sum rules. We construct the P-wave
baryon currents with a covariant derivative, and perform spin projection to obtain the currents with total spin 1/2 and 3/2. We then apply the parity-projected QCD sum rules to separate the contributions of the positive and negative parity states. We extract the masses of
and
states to be
GeV and
GeV. Both results are in good agreement with the experimental result. Therefore, it is likely that the
is a negative parity state, which is interpreted as a P-wave excited state in the quark model. However, its spin is not determined in the present analysis, which can be done by detailed study on its decay properties.
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:34.73(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.

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:6 パーセンタイル:74.40(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。
10
W/cm
Skobelev, I. Yu.*; Ryazantsev, S. N.*; Kulikov, R. K.*; Sedov, M. V.*; Filippov, E. D.*; Pikuz, S. A.*; 浅井 孝文*; 金崎 真聡*; 山内 知也*; 神野 智史; et al.
Photonics (Internet), 10(11), p.1250_1 - 1250_11, 2023/11
被引用回数:4 パーセンタイル:35.48(Optics)物質が高強度レーザーパルスと相互作用して生成されるプラズマの電荷状態の発展において、光電場と衝突電離の影響を明確に区別することは困難である。この研究では、プラズマキネティクスの時間依存計算を用いて、クラスターが十分に小さい低密度のガス状ターゲットを用いた場合にのみ可能であることを示した。Arプラズマの場合、クラスター半径の上限は
mと見積もられた。
and 
Xi, H.-Z.*; Jiang, Y.-W.*; Chen, H.-X.*; 保坂 淳; Su, N.*
Physical Review D, 108(9), p.094019_1 - 094019_13, 2023/11
被引用回数:11 パーセンタイル:62.38(Astronomy & Astrophysics)
と
の量子数をもつ、ストレンジクォークのみからなるテトラクォークを理論的に調べた結果を報告する。前者および後者の質量はそれぞれ2.47GeV、3.07GeVであるなど、いくつかの予言値を得た。
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:39 パーセンタイル:94.91(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。
Mo hot atoms made by a neutron capture method from
-MoO
to waterQuach, N. M.*; Ngo, M. C.*; Yang, Y.*; Nguyen, T. B.*; Nguyen, V. T.*; 藤田 善貴; Do, T. M. D.*; 中山 忠親*; 鈴木 達也*; 末松 久幸*
Journal of Radioanalytical and Nuclear Chemistry, 332(10), p.4057 - 4064, 2023/10
被引用回数:5 パーセンタイル:56.11(Chemistry, Analytical)テクネチウム-99m(
Tc)は世界で最も広く使用されている医療用ラジオアイソトープであり、モリブデン-99(
Mo)から生成される。核不拡散の観点から中性子放射化法による
Mo生成は核分裂由来の
Moの代替法として注目を集めているが、
Mo比放射能が極めて低いという欠点が存在する。本研究では、
Mo抽出による比放射能向上を目的に、照射ターゲットとしてポーラス
-MoO
ワイヤーを準備した。ポーラス
-MoO
ワイヤーは、2段階の加熱手順によって金属Moワイヤーから調製する。中性子照射後のポーラス
-MoO
ワイヤーおよび抽出に用いた水の放射能測定と同位体測定から
Moのホットアトム効果を確認した。また、ポーラス
-MoO
ワイヤーと市販の
-MoO
粉末での
Mo抽出率を比較した結果、同等の抽出率が得られた。