Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
-ray halo beyond 100 TeV雨森 道紘*; 瀧田 正人*; 土屋 晴文; Tibet AS Collaboration*; 他78名*
Science Advances (Internet), 12(10), p.eadv8173_1 - eadv8173_6, 2026/03
The extended -ray halo surrounding an old pulsar wind nebula (PWN) is an ideal place to investigate both theacceleration and diffusion processes of cosmic rays. In this work, we report the -ray halo observed with high precision by the Tibet AS experiment at the world/s highest-energy above 100 tera-electron volt (TeV). We determined the acceleration limit at about 100 TeV, beyond which the electron/positron flux suppresses exponentially,while we measured the morphology of the -ray halo at three different energies. We also found that the energy dependence of the diffusion coefficient is consistent with the Kolmogorov magnetohydrodynamic (MHD) turbulence and determined the turbulence property at scales smaller than 1 parsec. The measurements indicate thatthe energy of electrons/positrons is insufficient to amplify the strong MHD turbulence around itself, thereby suppressing the diffusion coefficient.
酒井 英明*; 木俣 基; 他7名*
Nature Communications (Internet), 16, p.11112_1 - 11112_8, 2026/01
被引用回数：0 パーセンタイル：0.00(Multidisciplinary Sciences)We report two-fold nonreciprocal angular magnetoresistance in the tetragonal layered Dirac material SrMnBi
with parity-time-symmetric antiferromagnetic order in its Mn-Bi layers. By quantitatively modelling the angular and field dependencies using a phenomenological framework, we reveal that the observed nonreciprocal interlayer resistivity arises from the current-induced breaking of four-fold rotoinversion symmetry of the Dirac valleys in the Bi square net adjacent to the Mn-Bi layer. Furthermore, we demonstrate the alignment of parity-time-symmetric antiferromagnetic domains via current-field cooling, achieving electric-magnetic control of the f-wave polarity in momentum space. The observed switchable nonreciprocal transport associated with current-tuneable valley nematicity paves the way for novel antiferromagnetic spintronic and valleytronic applications.
K
nstle, K.*; 山本 慧; 他7名*
Nature Communications (Internet), 16, p.10116_1 - 10116_8, 2025/11
被引用回数：0 パーセンタイル：0.00(Multidisciplinary Sciences)Strong coupling between distinct quasiparticles in condensed matter systems gives rise to hybrid states with emergent properties. We demonstrate the hybridization of confined phonons and finite-wavelength magnons, forming a magnon-polaron cavity with tunable coupling strength and spatial confinement controlled by the applied magnetic field direction. Our platform consists of a low-loss, single-crystalline yttrium iron garnet (YIG) film coupled to a zinc oxide (ZnO)-based surface acoustic wave (SAW) resonator. This heterostructure enables exceptionally low magnon-polaron dissipation rates below 
/2
1.5 MHz. The observed mode hybridization is well described by a phenomenological model incorporating the spatial profiles of magnon and phonon modes. Furthermore, we report the first observation of Rabi-like oscillations in a coupled SAW-spin wave system, revealing the dynamical formation of magnon-polarons in the time domain. These results establish a platform for engineering hybrid spin-acoustic excitations in extended magnetic systems and enable time-resolved studies of magnon-polaron states.
/
for the 19.40-MeV state in 
Be for studying the 
Be(
,
)Li
reaction relevant to the cosmological lithium problem岩佐 直仁*; 西尾 勝久; 廣瀬 健太郎; 牧井 宏之; Orlandi, R.; 洲嵜 ふみ; Smallcombe, J.; 他7名*
Physical Review C, 112(3), p.035801_1 - 035801_6, 2025/09
被引用回数：1 パーセンタイル：67.88(Physics, Nuclear)The Li(
He,
)Be(
)Li reaction was measured at 
(He) = 28 MeV for studying the Be(,)Li reaction, which is a Be destruction reaction in the big bang nucleosynthesis. Resonant states at 18.9
20.1 MeV in Be were populated by the Li(He,)Be reaction and decay protons to the ground (
) and first-excited states () in Li were well separated and measured. The resonance width 
and branching ratio / for the 19.40-MeV state in Be were deduced to be 342
112 keV and 11.2 3.5 5.0 (syst.)%, respectively. The 
Be(,)Li reaction cross section was deduced.
堀内 皓斗*; 荒木 康史; 若林 勇希*; 家田 淳一; 山ノ内 路彦*; 他7名*
Advanced Materials, 37(26), p.2416091_1 - 2416091_9, 2025/07
被引用回数：4 パーセンタイル：82.89(Chemistry, Multidisciplinary)Spin Berry curvature characterizes the band topology as the spin counterpart of Berry curvature and is crucial in generating novel spintronics functionalities. By breaking the crystalline inversion symmetry, the spin Berry curvature is expected to be significantly enhanced; this enhancement will increase the intrinsic spin Hall effect in ferromagnetic materials and, thus, the spin-orbit torques (SOTs). However, this intriguing approach is not applied to devices; generally, the spin Hall effect in ferromagnet/heavy-metal bilayer is used for SOT magnetization switching. Here, SOT-induced partial magnetization switching is demonstrated in a single layer of a single-crystalline Weyl oxide SrRuO
(SRO) with a small current density of 
. Detailed analysis of the crystal structure in the seemingly perfect periodic lattice of the SRO film reveals barely discernible oxygen octahedral rotations with angles of 
near the interface with a substrate. Tight-binding calculations indicate that a large spin Hall conductivity is induced around small gaps generated at band crossings by the synergy of inherent spin-orbit coupling and band inversion due to the rotations, causing magnetization reversal. The results indicate that a minute atomic displacement in single-crystal films can induce strong intrinsic SOTs that are useful for spin-orbitronics devices.
Wang, Y.*; Gong, W.; Harjo, S.; 他7名*
Acta Materialia, 288, p.120840_1 - 120840_14, 2025/04
被引用回数：17 パーセンタイル：98.93(Materials Science, Multidisciplinary)Low yield strength and the presence of Luders bands constitute principal impediments to the extensive applications of conventional medium Mn steels with a duplex microstructure of ferrite and austenite. Flash heating and the concept of chemical heterogeneity have been combined to engineer a duplex austenite-martensite microstructure in medium Mn steels, which has proven effective in augmenting the yield strength and mitigating the occurrence of Luders bands. However, the underlying mechanisms remain ambiguous. In the present work, the effect of austenite stability on yielding behavior was systematically investigated in an austenite-martensite duplex medium Mn steel. Austenite stability was identified as the critical factor governing yield strength, where reduced stability promotes early stage deformation induced martensite transformation, thereby decreasing yield strength. Diminished austenite stability may as well induce enhanced work hardening, thereby result in the inclination and eventual elimination of yield plateau, concomitant with the disappearance of Luders bands. These observations expand our current understanding of the yielding behavior in medium Mn steels and offer insights for the design of other advanced high strength steels.
Sanfilippo, A.*; 安邊 啓明; 他27名*
Nature Communications (Internet), 16, p.2016_1 - 2016_11, 2025/02
被引用回数：5 パーセンタイル：93.23(Multidisciplinary Sciences)Mantle processes control plate tectonics and exert an influence on biogeochemical cycles. However, the proportion of the mantle accessible to sampling is minimal, and a significant portion of our knowledge is derived from xenoliths, orogenic peridotite massifs exposed on land, and abyssal peridotites. Sampling of in-situ sections of the mantle is extremely challenging because they are buried beneath a magmatic crust with its sedimentary cover. In this study, we report the lithological characteristics of two mantle sections from an embryonic, very young, (~3 Ma) oceanic basin drilled by the International Ocean Discovery Program (IODP) in the central Tyrrhenian Sea. In contrast to observations made in drilled mantle sections from Mid Ocean Ridges (MORs) and hyperextended passive margins such as those in Iberia and Newfoundland, our findings revealed an exceptionally heterogeneous and generally fertile mantle. This represents a snapshot of young oceanic basement in a continental rifting environment characterised by general igneous starvation. The lithological heterogeneity ranges from fertile lherzolites to depleted harzburgites and dunites, variably interlayered with pyroxenites. Plagioclase- and clinopyroxene-rich layers, hydrous potassic magmatic veins, and gabbroic intrusions in these peridotites indicate substantial mantle re-fertilization and delayed inception of magmatic crust. The diverse lithological recovery indicates that magma-poor rifts do not necessarily require a chemically depleted mantle, too refractory to melt. Instead, we propose that deep lithospheric processes such as mantle refertilisation and prolonged lithospheric thinning hinder melt focusing and the formation of a steady-state spreading centre.
Marzec, E.*; 百々 拓; 羽賀 勝洋; 原田 正英; 長谷川 勝一; 春日井 好己; 木下 秀孝; 増田 志歩; 明午 伸一郎; 酒井 健二; et al.
Physical Review Letters, 134(8), p.081801_1 - 081801_9, 2025/02
被引用回数：5 パーセンタイル：90.55(Physics, Multidisciplinary)We present the first measurement of the missing energy due to nuclear effects in monoenergetic, muon neutrino charged-current interactions on carbon, originating from 
decay at rest (
), performed with the J-PARC Sterile Neutrino Search at the J-PARC Spallation Neutron Source liquid scintillator based experiment. Toward characterizing the neutrino interaction, ostensibly 
or 
C 
N, we define the missing energy as the energy transferred to the nucleus (
) minus the kinetic energy of the outgoing proton(s), 
, and relate this to visible energy in the detector, ![$$E_m = E_{nu_{mu}} (235.5 MeV) - m_{mu}(105.7 MeV) + [m_n - m_p(1.3 MeV)] - E_{vis}$$](/search/images/ERCV41JAHUQEKX11LRXHKX11LRWXK5L3EAUDEMZVFY0SATLFKYUSALJANVPXWXDNOV4SQMJQGUXDOICNMVLCSIBLEBNW0X1OEAWSA1K5OAUDCLRTEBGWKVRJLUQC0ICFL33XM0LTPUSA.gif)
. The missing energy, which is naively expected to be zero in the absence of nuclear effects (e.g., nucleon separation energy, Fermi momenta, and final-state interactions), is uniquely sensitive to many aspects of the interaction, and has previously been inaccessible with neutrinos. The shape-only, differential cross section measurement reported, based on a 
pure double-coincidence kaon decay-at-rest signal (621 total events), provides detailed insight into neutrino-nucleus interactions, allowing even the nuclear orbital shell of the struck nucleon to be inferred. The measurement provides an important benchmark for models and event generators at hundreds of MeV neutrino energies, characterized by the difficult-to-model transition region between neutrino-nucleus and neutrino-nucleon scattering, and relevant for applications in nuclear physics, neutrino oscillation measurements, and Type-II supernova studies.
GeTe
nanomeshes小幡 玲二*; 吉川 貴史*; 齊藤 英治; 他7名*
Nanotechnology, 35(47), p.475601_1 - 475601_9, 2024/11
被引用回数：2 パーセンタイル：14.28(Nanoscience & Nanotechnology)The growth of two-dimensional van der Waals magnetic materials presents attractive opportunities for exploring new physical phenomena and valuable applications. Among these materials, FeGeTe (FGT) exhibits a variety of remarkable properties and has garnered significant attention. Herein, we have for the first time created a nanomesh structure-a honeycomb-like array of hexagonal nanopores-with the zigzag pore-edge atomic structure on thin FGT flakes with and without oxidation of the pore edges. It is revealed that the magnitude of ferromagnetism (FM) significantly increases in both samples compared with bulk flakes without nanomeshes. Critical temperature annealing results in the formation of zigzag pore edges and interpore zigzag-edge nanoribbons. We unveil that the non-oxide (O) termination of the Fe dangling bonds on these zigzag edges enhances FM behavior, while O-termination suppresses this FM by introducing antiferromagnetic behavior through edge O-Fe coupling. FGT nanomeshes hold promise for the creation of strong FM and their effective application in magnetic and spintronic systems.
小澤 孝拓*; 福谷 克之; 他7名*
Nature Communications (Internet), 15, p.9558_1 - 9558_8, 2024/11
被引用回数：4 パーセンタイル：34.72(Multidisciplinary Sciences)Hydrogen, the smallest and lightest element, readily permeates a variety of materials and modulates their physical properties. Identification of the hydrogen lattice location and its amount in crystals is key to understanding and controlling the hydrogen-induced properties. Combining nuclear reaction analysis (NRA) with the ion channeling technique, we experimentally determined the locations of H and D in epitaxial nanofilms of titanium hydrides from the analysis of the two-dimensional angular mappings of NRA yields. Here we show that 11 at% of H are located at the octahedral site with the remaining H atoms in the tetrahedral site. Density functional theory calculations revealed that the structures with the partial octahedral site occupation are stabilized by the Fermi level shift and Jahn-Teller effect induced by hydrogen. In contrast, D was found to solely occupy the tetrahedral site owing to the mass effect on the zero-point vibrational energy. These findings suggest that site occupation of hydrogen can be controlled by changing the isotope mixture ratio, which leads to promising manifestation of novel hydrogen-related phenomena.
Garnaud, L.*; 小川 達彦; 他7名*
EPJ Web of Conferences, 302, p.07004_1 - 07004_14, 2024/10
被引用回数：3 パーセンタイル：96.46(Computer Science, Interdisciplinary Applications)光核反応によって生成される光中性子は、高エネルギーガンマ線源、電子加速器、または原子炉を用いる様々な分野で発生する。光中性子の放出をシミュレートし、その場を特性評価し、あるいは核システムへの影響を評価するため、一般的にモンテカルロ粒子輸送コードが使用される。本研究の目的は、複数のモンテカルロコード(MCNP6、PHITS、およびTRIPOLI-4)を用いて光中性子のシミュレーションに関するデータ集を作成することである。各コードは、ENDF/B-VIII.0およびJENDL-5核データライブラリを用いて順次実行される。反応エネルギー閾値から30MeVまで、すなわち巨大双極子共鳴(GDR)の領域において、自然同位体組成を持つ50の元素によって生成される光中性子場を扱った。光中性子場は、光中性子電流、エネルギースペクトル、および角度分布という3つの観測量に従って特性評価した。本稿では、原子番号の昇順で最初の5つの元素、すなわち重水素、ベリリウム、炭素、窒素、および酸素について得られた結果を提示した。
HfAlayed, B.*; Page, R. D.*; Joss, D. T.*; Uusitalo, J.*; Qi, C.*; Briscoe, A. D.*; AlAqeel, M. A. M.*; Andel, B.*; Antalic, S.*; Auranen, K.*; et al.
Physical Review C, 110(3), p.034303_1 - 034303_9, 2024/09
被引用回数：2 パーセンタイル：51.65(Physics, Nuclear)Excited states in the neutron-deficient nuclide Hf have been investigated in experiments performed at the Accelerator Laboratory of the University of Jyvaskyla.
Peri
ez, R.*; Bezhenar, R.*; Maderych, V.*; Brovchenko, I.*; Liptak, L.*; 小林 卓也; Min, B.-I.*; Suh, K. S.*; Little, A.*; Iosjpe, M.*; et al.
IAEA-TECDOC-2060, 55 Pages, 2024/07
IAEAは、2016年から2019年にかけて、放射線影響評価のためのモデリングとデータに関する(MODARIA II)プログラムを組織した。MODARIA IIの第7作業部会「海洋環境に放出された放射性核種の移行挙動の評価」では、拡散モデルを使用した海洋環境における放射性核種のシミュレーションに関する一般情報をまとめた。そして、東京電力福島第一原子力発電所事故シナリオを用いてCs-137の広域シミュレーションと生物への移行について検討するとともに、大西洋シナリオとして、ヨーロッパの核燃料使用済施設からの歴史的な放出について検討した。最後に、ラグランジェモデルにおける補間スキームの試験を実施した。本書は第7作業部会の活動内容について述べたものである。
Bi isotopesHuang, H.*; Andreyev, A. N.; 他37名*
Physical Review C, 110(1), p.014326_1 - 014326_8, 2024/07
被引用回数：3 パーセンタイル：64.72(Physics, Nuclear)The near-symmetric complete fusion reaction 
Kr+
Ag=
Bi was studied at the gas-filled recoil separator SHANS with an attempt to synthesize the extremely neutron-deficient proton-unbound Bi isotopes. No decay events which could be attributed to them were observed. The two- and three-particle evaporation residues 
Hg (
, 
) and 
Pb(
,
) were identified. Based on the yields of 182,183Pb in the present work and the systematics of the ratios between the cross sections of 
and 
evaporation channels for the most neutron-deficient odd-Z nuclei above lead, the upper limits for the half-lives of Bi were estimated to be less than 0.3
s.
長江 大輔*; 阿部 康志*; 山口 由高*; 洲嵜 ふみ; 他27名*
Physical Review C, 110(1), p.014310_1 - 014310_13, 2024/07
被引用回数：9 パーセンタイル：91.06(Physics, Nuclear)A dedicated isochronous storage ring, named the Rare-RI Ring, was constructed at the RI Beam Factory of RIKEN, aiming at precision mass measurements of nuclei located in uncharted territories of the nuclear chart. The Rare-RI Ring employs the isochronous mass spectrometry technique with the goal to achieve a relative mass precision of 10
within a measurement time of less than 1 ms. The performance of the facility was demonstrated through mass measurements of neutron-rich nuclei with well-known masses. Velocity or magnetic rigidity is measured for every particle prior to its injection into the ring, wherein its revolution time is accurately determined. The latter quantity is used to determine the mass of the particle, while the former one is needed for nonisochronicity corrections. Mass precisions on the order of 10
were achieved in the first commissioning, which demonstrates that the Rare-RI Ring is a powerful tool for mass spectrometry of short-lived nuclei.
ScZidarova, R.*; 宇都野 穣; 他76名*
Physica Scripta, 99(7), p.075309_1 - 075309_9, 2024/06
被引用回数：0 パーセンタイル：0.00(Physics, Multidisciplinary)理化学研究所のRIビームファクトリーにて
Sc(,)Sc反応によってScの励起状態を生成し、そこからの脱励起ガンマ線の放出を測定することによってその原子核のエネルギー準位を構築した。1510(30)keVの励起準位など、いくつかの新しい準位を見つけた。その結果を大規模殻模型計算の結果と比較し、ガンマ崩壊様式を考慮した結果、1510(30)keVの準位は
の可能性が高いことがわかった。
decay of the ground state and of a low-lying isomer in 
BiAndel, B.*; Andreyev, A. N.; 他57名*
Physical Review C, 109(6), p.064321_1 - 064321_18, 2024/06
被引用回数：4 パーセンタイル：74.27(Physics, Nuclear)A detailed -decay study of the low- and high-spin states in Bi has been performed at the ISOLDE Decay Station at the CERN-ISOLDE facility. In total, 48 new levels and 83 new transitions in the -decay daughter Po were identified. Shell-model calculations for excited states in Bi and Po were performed using the H208 and the modified Kuo-Herling particle effective interactions. Based on the experimental observations and the shell-model calculations, the most likely spin and parity assignments for the -decaying states in Bi are (3
) and (8), respectively.
substrate小幡 玲二*; 齊藤 英治; 吉川 貴史; 他7名*
Advanced Materials, 36(19), p.2311339_1 - 2311339_8, 2024/05
被引用回数：1 パーセンタイル：14.28(Chemistry, Multidisciplinary)SrTiO (STO) substrate, a perovskite oxide material known for its high dielectric constant (epsilon), facilitates the observation of various (high-temperature) quantum phenomena. A quantum Hall topological insulating (QHTI) state, comprising two copies of QH states with antiparallel two ferromagnetic edge-spin overlap protected by the U(1) axial rotation symmetry of spin polarization, has recently been achieved in low magnetic field (B) even as high as approximate to 100 K in a monolayer graphene/thin hexagonal boron nitride (hBN) spacer placed on an STO substrate, thanks to the high epsilon of STO. Despite the use of the heavy STO substrate, however, proximity-induced quantum spin Hall (QSH) states in 2D TI phases, featuring a topologically protected helical edge spin phase within time-reversal-symmetry, is not confirmed. Here, with the use of a monolayer hBN spacer, it is revealed the coexistence of QSH (at B = 0T) and QHTI (at B not equal 0) states in the same single graphene sample placed on an STO, with a crossover regime between the two at low B. It is also classified that the different symmetries of the two nontrivial helical edge spin phases in the two states lead to different interaction with electron-puddle quantum dots, caused by a local surface pocket of the STO, in the crossover regime, resulting in a spin dephasing only for the QHTI state. The results obtained using STO substrates open the doors to investigations of novel QH spin states with different symmetries and their correlations with quantum phenomena. This exploration holds value for potential applications in spintronic devices.
Zn+
U reactionBenito, J.*; Lenzi, S. M.*; Recchia, F.*; Axiotis, M.*; Aydin, S.*; Bazzacco, D.*; Benzoni, G.*; Orlandi, R.; 他37名*
Acta Physica Polonica B; Proceedings Supplement, 17(3), p.3-A4_1 - 3-A4_7, 2024/04
被引用回数：0 パーセンタイル：0.00(Physics, Multidisciplinary)Excited states of neutron-rich 
Fe isotopes have been studied through a multinucleon transfer reaction of a Zn beam on a U target at the National Laboratories of Legnaro, Italy. The magnetic spectrometer PRISMA was used to identified the isotopes produced in the reaction, and the CLARA array of Clover Ge detectors to detect their gamma rays. The obtained level scheme were compared with new, state-of-the-art large scale shell model calculations. The large model space used in the calculation, which included the 2d
orbital, revealed that this orbit is key in order to obtain excellent agreement between the calculations and the experimental data.
Schnabel, G.*; 国枝 賢; 今野 力; 中山 梓介; 他27名*
Nuclear Data Sheets, 193, p.1 - 78, 2024/02
被引用回数：26 パーセンタイル：99.27(Physics, Nuclear)国際原子力機関(IAEA)が中心となり、各国の研究者の協力のもと、核融合研究開発のための国際核データライブラリFENDLの更新を行った。最新ライブラリ(FENDL-3.2b)の構築にあたっては、主に米国のENDF、欧州のJEFF、日本のJENDLの相互比較を行い、積分検証結果も踏まえつつ、現状で最も妥当と考えられるデータを個々の核種毎に採用した。従来のライブラリとの大きな違いは、加速器中性子源やそれを用いる材料研究分野からのニーズに応えるためにこれまでのエネルギー上限を20MeVから最大200MeVに拡張し、中性子データのみならず陽子や重陽子データの収録も新規に行なったことである。また、本ライブラリの品質を検証することを目的として、中性子輸送計算や核発熱シミュレーション等を通じた種々のベンチーマーク解析を実施した。それにより、従来のライブラリに比べ実用性が大きく向上していることを示した。
