Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
CuPedersen, L. G.*; Sahin, E.*; G
rgen, A.*; Bello Garrote, F. L.*; 角田 佑介*; 大塚 孝治*; 新倉 潤*; Orlandi, R.; 他59名*
Physical Review C, 107(4), p.044301_1 - 044301_10, 2023/04
Nuclei in the vicinity of Ni (
=28, 
=50) are important benchmarks to study the evolution of shell structure far from stability. Excited states in Cu were observed for the first time following the 
-decay of Ni, which was produced by in-flight fission of 
U. Using 
-ray coincidences, a level scheme comprising eight excited states was built. Using the observed feeding and the -decay properties of the excited states, spin was tentatively assigned to 5 new states. In addition to the -decaying states, an isomeric state with a lifetime of 3.8(4) ms was found to decay by internal conversion. By comparing the results with large scale shell model calculations, quantitative information about the proton-neutron interaction outside the doubly magic Ni core was obtained.
elastic scattering in the momentum range 0.44-0.80 GeV/c七村 拓野; 藤田 真奈美; 長谷川 勝一; 市川 真也; 市川 裕大; 今井 憲一*; 成木 恵; 佐藤 進; 佐甲 博之; 田村 裕和; et al.
Progress of Theoretical and Experimental Physics (Internet), 2022(9), p.093D01_1 - 093D01_35, 2022/09
被引用回数：1 パーセンタイル：52.46(Physics, Multidisciplinary)We performed a novel 
scattering experiment at the J-PARC Hadron Experimental Facility. Approximately 2400 elastic scattering events were identified from 
tagged 
particles in the momentum range 0.44 - 0.80 GeV/c. The differential cross sections of the elastic scattering were derived with much better precision than in previous experiments. The obtained differential cross sections were approximately 2 mb/sr or less, which were not as large as those predicted by the fss2 and FSS models based on the quark cluster model in the short-range region. By performing phase-shift analyses for the obtained differential cross sections, we experimentally derived the phase shifts of the 
and 
channels for the first time. The phase shift of the 3S1 channel, where a large repulsive core was predicted owing to the Pauli effect between quarks, was evaluated to be 
. If the sign of 
is assumed to be negative, the interaction in this channel is moderately repulsive, as the Nijmegen extended-sort-core models predicted.
isomeric state in 
TlVenhart, M.*; Andreyev, A. N.; Cubiss, J. G.*; Wood, J. L.*; Barzakh, A. E.*; Van Beveren, C.*; Cocolios, T. E.*; de Groote, R. P.*; 他19名*
Physical Review C, 105(3), p.034338_1 - 034338_9, 2022/03
被引用回数：1 パーセンタイル：56.18(Physics, Nuclear)The neutron-deficient region of isotopes around =82 is the best studied example of low-energy shape coexistence in nuclei. In this work, the internal transition decay and 
decay of the 53.3-ms isomeric state in Tl were studied at ISOLDE, CERN. The branching for the internal decay was measured to be 98.5(4)%, while the much weaker decay branching is only about 1.4(4)%. The new results include the first identification of an 
transition feeding the 3/2
excited state in Tl. Three decays from the 
Tl isomer were also oserved, and revealed the population of a candidate 9/2 state in 
Au which has been linked to shape coexistence in the Au nuclei. It is expected that similarly weak decays from isomeric states may be found also in neighbouring Tl isotopes.
中村 智樹*; 大澤 崇人; 他219名*
Science, 24 Pages, 2022/00
1から8mmのリュウグウ粒子16個の鉱物学的,岩石学的、および物理的特性は、それらがCIコンドライトに最も類似していることを示している。磁硫鉄鉱中のCO
含有水の存在は、母天体が太陽系星雲のHOおよびCOのスノーラインを越えた領域で形成したことを示しており、ここでは、リュウグウの鉱物学に基づくと、小さなコンドリュールやCa, Alを含む非常に限られた量の高温物質がある。流体-岩石反応は、低温,高pH、および水/岩石の質量比が1未満の還元条件で発生し、リュウグウのサンプルで最も変化の少ない断片として残っているかんらん石-輝石に富む岩相を、リュウグウサンプルの主要な岩相であるフィロケイ酸塩-炭酸塩に富むものに変えた。リュウグウの母体の流体から磁鉄鉱が結晶化したとき、原始太陽系星雲はまだ存在していた可能性がある。
外山 健*; 鈴土 知明; 永井 康介*; 他9名*
Journal of Nuclear Materials, 556, p.153176_1 - 153176_7, 2021/12
被引用回数：2 パーセンタイル：46.88(Materials Science, Multidisciplinary)電子照射と3次元アトムプローブ(3D-AP)を使用して、照射促進拡散(RED)の高精度測定を行った。高純度のFeとCuをベース材料としてCu-Fe拡散ペア試料を作成し、2MeVの電子照射を行った。CuのFeマトリックスへの拡散を3D-APを使用して原子レベルで観察し、フィックの法則を使用して拡散係数を直接取得した。その結果、REDが明確に観察され、照射下での拡散と熱拡散の比率が低温で大きくなった。反応速度論モデルを使用してREDを定量的に評価し、実験値は空孔のみを考慮したモデルと良好な一致を示した。これにより、REDが照射誘起空孔によって支配されていることが明らかになった。さらに、FeへのCuの溶解度に対する照射の影響に関する直接的な実験結果が得られ、照射下での溶解度は、熱時効下での溶解度よりも低いことがわかった。
decaysCao, L.*; 谷田 聖; Belle Collaboration*; 他199名*
Physical Review Letters, 127(26), p.261801_1 - 261801_8, 2021/12
被引用回数：1 パーセンタイル：23.97(Physics, Multidisciplinary)The first measurements of differential branching fractions of inclusive semileptonic decays are performed using the full Belle data set of 711 fb
of integrated luminosity at the 
resonance and for 
. Differential branching fractions are reported as a function of the lepton momentum, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting the backgrounds from semileptonic 
decays and other processes, and corrected for resolution and acceptance effects. The measured distributions are compared to predictions from inclusive and hybrid calculations.
(
) with a hadronic tagging method at BelleAtmacan, H.*; 谷田 聖; Belle Collaboration*; 他219名*
Physical Review D, 104(9), p.L091105_1 - L091105_9, 2021/11
被引用回数：1 パーセンタイル：15.91(Astronomy & Astrophysics)We present a search for the lepton-flavor-violating decays , where 
, using the full data sample of 
pairs recorded by the Belle detector at the KEKB asymmetric-energy 
collider. We use events in which one 
meson is fully reconstructed in a hadronic decay mode. The 
lepton is reconstructed indirectly using the momentum of the reconstructed and that of the 
from the signal decay. We find no evidence for decays and set upper limits on their branching fractions at 90% confidence level of 
(
)
and (
)
.
decay at BelleLi, S. X.*; 谷田 聖; Belle Collaboration*; 他193名*
Physical Review D, 104(7), p.072008_1 - 072008_8, 2021/10
被引用回数：3 パーセンタイル：41.31(Astronomy & Astrophysics)Using 980.6 
of data collected with the Belle detector operating at the KEKB asymmetric-energy collider, we present a measurement of the branching fraction of the singly Cabibbo-suppressed decay . A clear 
signal is observed for with a statistical significance of 9.1 standard deviations, and we measure the ratio of branching fractions 
, from which we infer the branching fraction 
. The first quoted uncertainty is statistical, the second systematic, and the third from the reference mode 
.
Li, Y.*; 谷田 聖; Belle Collaboration*; 他190名*
Physical Review D, 104(5), p.052005_1 - 052005_9, 2021/09
被引用回数：4 パーセンタイル：50.79(Astronomy & Astrophysics)Using a data sample of 980~fb collected with the Belle detector operating at the KEKB asymmetric-energy collider, we present evidence for the 
in the resonant substructure of 
(
= 
+ 
) decays. The significance of the signal is 4.2
after considering the systematic uncertainties. The ratio of the branching fraction of 
relative to that of 
is calculated to be 0.220 
0.059(stat.) 0.035(syst.). The individual ratios of the branching fractions of the two isospin modes are also determined, and found to be 
=(9.6 3.2(stat.) 1.8(syst.))% and 
= (5.5 2.8(stat.) 0.7(syst.))%.
Nisar, N. K.*; 谷田 聖; Belle Collaboration*; 他197名*
Physical Review D, 104(3), p.L031101_1 - L031101_8, 2021/08
被引用回数：0 パーセンタイル：0.01(Astronomy & Astrophysics)We report the results of the first search for the decay using 
of data collected at the 
resonance with the Belle detector at the KEKB asymmetric-energy collider. We observe no significant signal and set a 90% confidence-level upper limit of 
on the branching fraction of this decay.
= 510 GeV proton-proton collisions佐藤 健太*; 谷田 聖; 他19名*
Proceedings of Science (Internet), 358, p.413_1 - 413_8, 2021/07
The Relativistic Heavy Ion Collider forward (RHICf) experiment aims at understanding the high-energy hadronic interaction by measuring the cross sections of very forward neutral particles in proton-proton collisions at = 510 GeV. For the analysis of the photon measurement, the trigger efficiency and the particle identification performance are studied by using the Monte Carlo simulation data and the experimental data. In the RHICf operation, two kinds of trigger modes (Shower, HighEM) were implemented. The trigger efficiency of the Shower trigger is 100% for photons with the energies more than 20 GeV. The HighEM trigger is designed to detect high energy photons effectively, and the trigger efficiency of the HighEM trigger is 90% for photons with the energies more than 130 GeV. The correction factor for the photon identification is calculated by using the efficiency and purity. It is found that this correction does not make a sizeable effect on the shape of the energy spectrum because the energy dependency of the factor is small.
McNeil, J. T.*; 谷田 聖; Belle Collaboration*; 他193名*
Physical Review D, 103(11), p.112002_1 - 112002_11, 2021/06
被引用回数：2 パーセンタイル：29.64(Astronomy & Astrophysics)Using the entire data sample of 
integrated luminosity collected with the Belle detector at the KEKB asymmetric-energy 
collider, we present an amplitude analysis measuring the branching fractions of the Cabibbo-allowed, 
-exchange resonant decay 
with a polarized 
and the non-resonant decay via a direct process . We present these measurements, relative to the normalization mode 
, and find branching ratios 
= 
and 
= 
which suggest that only minor cusping peaks occur in the combinatorial background of 
due to these 
decays.
雨森 道紘*; 土屋 晴文; Tibet AS
Collaboration*; 他93名*
Nature Astronomy (Internet), 5(5), p.460 - 464, 2021/05
被引用回数：34 パーセンタイル：97.83(Astronomy & Astrophysics)Cosmic rays (protons and other atomic nuclei) are believed to gain energies of petaelectronvolts (PeV) and beyond at astrophysical particle accelerators called "PeVatrons" inside our Galaxy. Although a characteristic feature of a PeVatron is expected to be a hard gamma-ray energy spectrum that extends beyond 100 teraelectronvolts (TeV) without a cut-off, none of the currently known sources exhibit such a spectrum owing to the low maximum energy of accelerated cosmic rays or owing to insufficient detector sensitivity around 100 TeV. Here, we report the observation of gamma-ray emission from the supernova remnant G106.3+2.7 above 10 TeV. This work provides flux data points up to and above 100 TeV and indicates that the very-high-energy gamma-ray emission above 10 TeV is well correlated with a molecular cloud rather than with the pulsar PSR J2229+6114. Regarding the gamma-ray emission mechanism of G106.3+2.7, this morphological feature appears to favour a hadronic origin via the 
decay caused by accelerated relativistic protons over a leptonic origin via the inverse Compton scattering by relativistic electrons. Furthermore, we point out that an X-ray flux upper limit on the synchrotron spectrum would provide important information to firmly establish the hadronic scenario as the mechanism of particle acceleration at the source.
decays at BelleWehle, S.*; 谷田 聖; Belle Collaboration*; 他179名*
Physical Review Letters, 126(16), p.161801_1 - 161801_8, 2021/04
被引用回数：10 パーセンタイル：79.66(Physics, Multidisciplinary)We present a measurement of 
, the branching fraction ratio 
/ 
, for both charged and neutral mesons. The ratio for the charged case, 
, is the first measurement ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass, 
. The analysis is based on a data sample of 
, containing 
events, recorded at the resonance with the Belle detector at the KEKB asymmetric-energy collider. The obtained results are consistent with Standard Model expectations.
雨森 道紘*; 土屋 晴文; Tibet AS Collaboration*; 他93名*
Physical Review Letters, 126(14), p.141101_1 - 141101_7, 2021/04
被引用回数：71 パーセンタイル：99.51(Physics, Multidisciplinary)We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of 
's produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.
and 
mesons in polarized 
collisions at 
GeVAcharya, U. A.*; 長谷川 勝一; 今井 憲一*; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他309名*
Physical Review D, 103(5), p.052009_1 - 052009_10, 2021/03
被引用回数：4 パーセンタイル：50.79(Astronomy & Astrophysics)We present a measurement of the transverse single-spin asymmetry for and mesons in 
collisions in the pseudorapidity range 
and at a center-of-mass energy of 200 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. In comparison with previous measurements in this kinematic region, these results have a factor of 3 smaller uncertainties. As hadrons, and mesons are sensitive to both initial- and final-state nonperturbative effects for a mix of parton flavors. Comparisons of the differences in their transverse single-spin asymmetries have the potential to disentangle the possible effects of strangeness, isospin, or mass. These results can constrain the twist-3 trigluon collinear correlation function as well as the gluon Sivers function.
and mesons in UU collisions at 
GeVAcharya, U.*; 長谷川 勝一; 今井 憲一*; 永宮 正治*; 佐甲 博之; 佐藤 進; 谷田 聖; PHENIX Collaboration*; 他397名*
Physical Review C, 102(6), p.064905_1 - 064905_13, 2020/12
被引用回数：4 パーセンタイル：53.73(Physics, Nuclear)The PHENIX experiment at the Relativistic Heavy Ion Collider measured and mesons at midrapidity in UU collisions at GeV in a wide transverse momentum range. Measurements were performed in the 
decay modes. A strong suppression of and meson production at high transverse momentum was observed in central UU collisions relative to binary scaled results. Yields of and mesons measured in UU collisions show similar suppression pattern to the ones measured in AuAu collisions at 
GeV for similar numbers of participant nucleons. The / ratios do not show dependence on centrality or transverse momentum, and are consistent with previously measured values in hadron-hadron, hadron-nucleus, nucleus-nucleus, and collisions.
and to 
and 
with emission of an 
mesonOskin, P.*; 谷田 聖; Belle Collaboration*; 他198名*
Physical Review D, 102(9), p.092011_1 - 092011_8, 2020/11
被引用回数：0 パーセンタイル：0.01(Astronomy & Astrophysics)Using data collected in the Belle experiment at the KEKB asymmetric-energy collider we search for transitions 
, 
and 
. No significant signals are observed and we set 90% confidence level upper limits on the corresponding visible cross sections: 
and 
, respectively.
AuCubiss, J. G.*; Andreyev, A. N.; Barzakh, A. E.*; Manea, V.*; Al Monthery, M.*; Althubiti, N. A.*; Andel, B.*; Antalic, S.*; 他39名*
Physical Review C, 102(4), p.044332_1 - 044332_12, 2020/10
被引用回数：5 パーセンタイル：61.45(Physics, Nuclear)A comprehensive study of the isotope Au has been made at the CERN-ISOLDE facility, using resonance laser ionization. Two long-lived states in Au were identified - a low-spin ground state and a high-spin isomer - each of which were produced as pure beams. Using the ISOLTRAP precision Penning trap, the excitation energy of the isomeric state in Au was determined to be 
189(14) keV. The -decay fine structure patterns of the two states were studied using the Windmill decay station, providing information on the low-lying states in the daughter nucleus 
Ir. Nuclear spin assignments of 
Au
and Au
are made based on the observed -decay feeding and hyperfine structure intensity patterns.
Sc
)
O
single crystals内海 重宣*; 田中 誠也*; 丸山 建一*; 天児 寧*; 鬼柳 亮嗣; 中尾 朗子*; 森山 健太郎*; 石川 喜久*; 他9名*
ACS Omega (Internet), 5(38), p.24890 - 24897, 2020/09
被引用回数：3 パーセンタイル：20.65(Chemistry, Multidisciplinary)六方晶フェライトBa(FeSc)Oの磁気構造を解明し、さらなる応用開発を進めるためには、大型の高品質な単結晶を育成することが重要な第一歩である。本研究では、NaO-FeO
フラックスを使用した自発結晶化法によって、さまざまなSc濃度
のBa(FeSc)O単結晶の育成に成功した。得られた結晶は、高品質の単相Ba(FeSc)OであることがX線回折と元素分析により確認され、 = 0.128結晶の77Kの磁化測定では、ヘリマグネティックな挙動を示すことがわかった。=0.128結晶の中性子回折測定の結果、211K以下で磁気衛星反射が確認され、Ba(FeSc)Oがヘリ磁性物質であることが確認された。
