JAEA
  • help
  • PC | SP
  • JP | EN
          
検索対象：     
報告書番号：
※ 半角英数字
 年 ～ 
 年
全てクリア
検索結果：　56 件中 1件目～20件目を表示

発表形式

Initialising ...

選択項目を絞り込む

掲載資料名

Initialising ...

発表会議名

Initialising ...

筆頭著者名

Initialising ...

キーワード

Initialising ...

発表言語

Initialising ...

発行年

Initialising ...

開催年

Initialising ...

選択した検索結果をダウンロード

論文

All-temperature barocaloric effects at pressure-induced phase transitions

Zhao, X.*; Zhang, Z.*; 服部 高典; Wang, J.*; Li, L.*; Jia, Y.*; Li, W.*; Xue, J.*; Fan, X.*; Song, R.*; et al.

Nature Communications (Internet), 16, p.7713_1 - 7713_8, 2025/08

https://doi.org/10.1038/s41467-025-63068-z
 被引用回数：0 パーセンタイル：0.00

熱効果は、固体状態の冷凍技術の一つの解決策の基盤を成すもので、通常は固体状態の相転移付近で発生し、冷凍温度範囲が限定されている。ここでは、前例のない概念である「全温度帯バロカロリック効果」を導入し実現する。すなわち、KPF$$_6$$において77.5Kから300Kの極めて広い温度範囲(潜在的に4Kまで)で観測される顕著なバカカロリック効果である。この温度範囲は、一般的な室温、液体窒素、液体水素、液体ヘリウムの冷却領域をカバーしている。直接測定されたバーカロリック断熱温度変化は、250MPaの圧力を解放した際に、室温で12K、77.5Kで2.5Kに達する。この効果は、圧力依存性の中性子粉末回折、ラマン散乱解析、第一原理計算により示されるように、菱面体高圧相への持続的な相転移に起因する。構造的不安定性を考慮した熱力学的エネルギーランドスケープを記述する。この独自の全温度帯バロカロリック効果は、従来の多段式シナリオを超えた、高度に適用可能な固体状態冷凍技術への新たなアプローチを提供する。

論文

Strong low-energy rattling modes enabled liquid-like ultralow thermal conductivity in a well-ordered solid

Liu, P.-F.*; Li, X.*; Li, J.*; Zhu, J.*; Tong, Z.*; 古府 麻衣子*; 楡井 真実; Xu, J.*; Yin, W.*; Wang, F.*; et al.

National Science Review, 11(12), p.nwae216_1 - nwae216_10, 2024/12

https://doi.org/10.1093/nsr/nwae216
 被引用回数：16 パーセンタイル：91.30(Multidisciplinary Sciences)

Crystalline solids exhibiting inherently low lattice thermal conductivity ($$kappa_{rm L}$$) are of great importance in applications such as thermoelectrics and thermal barrier coatings. However, $$kappa_{rm L}$$ cannot be arbitrarily low and is limited by the minimum thermal conductivity related to phonon dispersions. In this work, we report the liquid-like thermal transport in a well-ordered crystalline CsAg$$_5$$Te$$_3$$, which exhibits an extremely low $$kappa_{rm L}$$ value of $$sim$$ 0.18 Wm$$^{-1}$$K$$^{-1}$$. On the basis of first-principles calculations and inelastic neutron scattering measurements, we find that there are lots of low-lying optical phonon modes at $$sim$$ 3.1 meV hosting the avoided-crossing behavior with acoustic phonons. These strongly localized modes are accompanied by weakly bound rattling Ag atoms with thermally induced large amplitudes of vibrations. Using the two-channel model, we demonstrate that coupling of the particle-like phonon modes and the heat-carrying wave-like phonons is essential for understanding the low $$kappa_{rm L}$$, which is heavily deviated from the $$1/T$$ temperature dependence of the standard Peierls theory. In addition, our analysis indicates that the soft structural framework with liquid-like motions of the fluctuating Ag atoms is the underlying cause that leads to the suppression of the heat conduction in CsAg$$_5$$Te$$_3$$. These factors synergistically account for the ultralow $$kappa_{rm L}$$ value. Our results demonstrate that the liquid-like heat transfer could indeed exist in a well-ordered crystal.

論文

Antiferromagnetism and phase stability of CrMnFeCoNi high-entropy alloy

Zhu, L.*; He, H.*; Naeem, M.*; Sun, X.*; Qi, J.*; Liu, P.*; Harjo, S.; 中島 健次; Li, B.*; Wang, X.-L.*

Physical Review Letters, 133(12), p.126701_1 - 126701_6, 2024/09

https://doi.org/10.1103/PhysRevLett.133.126701
 被引用回数：4 パーセンタイル：72.86(Physics, Multidisciplinary)

It has long been suspected that magnetism could play a vital role in the phase stability of multi- component high-entropy alloys. However, the nature of the magnetic order, if any, has remained elusive. Here, by using elastic and inelastic neutron scattering, we demonstrate evidence of antiferromagnetic order below $$sim$$80 K and strong spin fluctuations persisting to room temperature in a single-phase face-centered cubic (fcc) CrMnFeCoNi high-entropy alloy. Despite the chemical complexity, the magnetic structure in CrMnFeCoNi can be described as $$gamma$$-Mn-like, with the magnetic moments confined in alternating (001) planes and pointing toward the $$langle$$111$$rangle$$ direction. Combined with first-principles calculation results, it is shown that the antiferromagnetic order and spin fluctuations help stabilized the fcc phase in CrMnFeCoNi high-entropy alloy.

論文

Low spin spectroscopy of neutron-rich $$^{43,44,45}$$Cl via $$beta^-$$ and $$beta n$$ decay

Tripathi, V.*; Bhattacharya, S.*; Rubino, E.*; Benetti, C.*; Perello, J. F.*; Tabor, S. L.*; Liddick, S. N.*; Bender, P. C.*; Carpenter, M. P.*; Carroll, J. J.*; et al.

Physical Review C, 109(4), p.044320_1 - 044320_15, 2024/04

https://doi.org/10.1103/PhysRevC.109.044320
 被引用回数：2 パーセンタイル：61.39(Physics, Nuclear)

ミシガン州立大学の国立超伝導サイクロトロン研究所において$$^{48}$$Caのフラグメンテーション反応によって中性子過剰核$$^{43,45}$$Sを生成し、そこからのベータ崩壊および遅発中性子放出ベータ崩壊によって$$^{43,44,45}$$Clの励起状態を得た。得られた実験データをSDPFSDG-MU相互作用を用いた大規模殻模型計算と比較し、よい一致を得た。

論文

Crystal-liquid duality driven ultralow two-channel thermal conductivity in $$alpha$$-MgAgSb

Li, J.*; Li, X.*; Zhang, Y.*; Zhu, J.*; Zhao, E.*; 古府 麻衣子; 中島 健次; Avdeev, M.*; Liu, P.-F.*; Sui, J.*; et al.

Applied Physics Reviews (Internet), 11(1), p.011406_1 - 011406_8, 2024/03

https://doi.org/10.1063/5.0173680
 被引用回数：13 パーセンタイル：92.16(Physics, Applied)

The desire for intrinsically low lattice thermal conductivity ($$kappa_L$$) in thermoelectrics motivates numerous efforts on understanding the microscopic mechanisms of heat transport in solids. Here, based on theoretical calculations, we demonstrate that $$alpha$$-MgAgSb hosts low-energy localized phonon bands and avoided crossing of the rattler modes, which coincides with the inelastic neutron scattering result. Using the two-channel lattice dynamical approach, we find, besides the conventional contribution ($$sim$$70% at 300 K) from particlelike phonons propagating, the coherence contribution dominated by the wavelike tunneling of phonons accounts for $$sim$$30% of total $$kappa_L$$ at 300 K. By considering dual contributions, our calculated room-temperature $$kappa_L$$ of 0.64 Wm$$^{-1}$$K$$^{-1}$$ well agrees with the experimental value of 0.63 Wm$$^{-1}$$K$$^{-1}$$. More importantly, our computations give a nonstandard $$kappa_L propto T^{-0.61}$$ dependence, perfectly explaining the abnormal temperature-trend of $$sim T^{-0.57}$$ in experiment for $$alpha$$-MgAgSb. By molecular dynamics simulation, we reveal that the structure simultaneously has soft crystalline sublattices with the metavalent bonding and fluctuating liquid-like sublattices with thermally induced large amplitude vibrations. These diverse forms of chemical bonding arouse mixed part-crystal part-liquid state, scatter strongly heat-carrying phonons, and finally produce extremely low $$kappa_L$$. The fundamental research from this study will accelerate the design of ultralow-$$kappa_L$$ materials for energy-conversion applications.

論文

Phase transformation and equation of state in Ti-45Al alloy under high pressure

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

https://doi.org/10.1016/j.calphad.2023.102641
 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 $$gamma$$ transforms continuously to $$alpha$$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 $$gamma$$ phase, 138 GPa for the $$alpha$$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 $$alpha$$2 and $$gamma$$ phases under high pressure.

論文

Extreme phonon anharmonicity underpins superionic diffusion and ultralow thermal conductivity in argyrodite Ag$$_{8}$$SnSe$$_{6}$$

Ren, Q.*; Gupta, M. K.*; Jin, M.*; Ding, J.*; Wu, J.*; Chen, Z.*; Lin, S.*; Fabelo, O.*; Rodriguez-Velamazan, J. A.*; 古府 麻衣子; et al.

Nature Materials, 22(8), p.999 - 1006, 2023/08

https://doi.org/10.1038/s41563-023-01560-x
 被引用回数：91 パーセンタイル：99.14(Chemistry, Physical)

Ultralow thermal conductivity and fast ionic diffusion endow superionic materials with excellent performance both as thermoelectric converters and as solid-state electrolytes. Yet the correlation and interdependence between these two features remain unclear owing to a limited understanding of their complex atomic dynamics. Here we investigate ionic diffusion and lattice dynamics in argyrodite Ag$$_{8}$$SnSe$$_{6}$$ using synchrotron X-ray and neutron scattering techniques along with machine-learned molecular dynamics. We identify a critical interplay of the vibrational dynamics of mobile Ag and a host framework that controls the overdamping of low-energy Ag-dominated phonons into a quasi-elastic response, enabling superionicity. Concomitantly, the persistence of long-wavelength transverse acoustic phonons across the superionic transition challenges a proposed 'liquid-like thermal conduction' picture. Rather, a striking thermal broadening of low-energy phonons, starting even below 50 K, reveals extreme phonon anharmonicity and weak bonding as underlying features of the potential energy surface responsible for the ultralow thermal conductivity ($$<$$ 0.5 Wm$$^{-1}$$K$$^{-1}$$) and fast diffusion. Our results provide fundamental insights into the complex atomic dynamics in superionic materials for energy conversion and storage.

論文

Chiral perturbation theory for heavy hadrons and chiral effective field theory for heavy hadronic molecules

Meng, L.*; Wang, B.*; Wang, G.-J.*; Zhu, S.-L.*

Physics Reports; A Review Section of Physics Letters, 1019, p.1 - 149, 2023/05

https://doi.org/10.1016/j.physrep.2023.04.003
 被引用回数：142 パーセンタイル：96.97(Physics, Multidisciplinary)

Chiral symmetry and its spontaneous breaking play an important role both in the light hadron and heavy hadron systems. The chiral perturbation theory ($$chi$$PT) is the low energy effective field theory of the Quantum Chromodynamics. In this work, we shall review the investigations on the chiral corrections to the properties of the heavy mesons and baryons within the framework of $$chi$$PT. We will also review the scatterings of the light pseudoscalar mesons and heavy hadrons, through which many new resonances such as the D*s0(2317) could be understood. Moreover, many new hadron states were observed experimentally in the past decades. A large group of these states is near-threshold resonances, such as the charged charmoniumlike $$Z_{c}$$ and $$Z_{cs}$$ states, bottomoniumlike $$Z_{b}$$ states, hidden-charm pentaquark $$P_{c}$$ and $$P_{cs}$$ states and the doubly charmed $$T_{cc}$$ state, etc. They are very good candidates of the loosely bound molecular states composed of a pair of charmed (bottom) hadrons, which are very similar to the loosely bound deuteron. The modern nuclear force was built upon the chiral effective field theory (LEFT), which is the extension of the $$chi$$PT to the systems with two matter fields. The long-range and medium-long-range interactions between two nucleons arise from the single-and double-pion exchange respectively, which are well constrained by the chiral symmetry and its spontaneous breaking. The short-distance interactions can be described by the low energy constants. Such a framework works very well for the nucleon-nucleon scattering and nuclei. In this work, we will perform an extensive review of the progress on the heavy hadronic molecular states within the framework of LEFT. We shall emphasize that the same chiral dynamics not only govern the nuclei and forms the deuteron, but also dictates the shallow bound states or resonances composed of two heavy hadrons.

論文

The Investigations of the $$P$$-wave $$B_s$$ states combining quark model and lattice QCD in the coupled channel framework

Yang, Z.*; Wang, G.-J.*; Wu, J.-J.*; 岡 眞; Zhu, S.-L.*

Journal of High Energy Physics (Internet), 2023(1), p.058_1 - 058_19, 2023/01

https://doi.org/10.1007/JHEP01(2023)058
 被引用回数：10 パーセンタイル：74.32(Physics, Particles & Fields)

ハミルトニアン有効理論にクォーク模型、クォークペア生成、$$B^{(*)}bar K$$相互作用の情報を含むベアな状態と散乱状態の結合を取り入れた形式を用いて、しきい値近傍の$$P$$波の4個の$$B_s$$状態のスペクトルを研究した。

論文

Study of $$e^{+}e^{-}toetaphi$$ via initial state radiation at Belle

Zhu, W. J.*; 谷田 聖; Belle Collaboration*; 他174名*

Physical Review D, 107(1), p.012006_1 - 012006_10, 2023/01

https://doi.org/10.1103/PhysRevD.107.012006
 被引用回数：2 パーセンタイル：25.23(Astronomy & Astrophysics)

Using $$980~fb^{-1}$$ of data collected on and around the $$Upsilon(nS)(n=1,2,3,4,5)$$ resonances with the Belle detector at the KEKB collider, we measure the cross section of $$e^{+}e^{-}to etaphi$$ from threshold to $$3.95~{rm GeV}/c^{2}$$ via initial-state radiation. From a multi-parameter fit assuming $$phi(2170)$$ exists in the $$etaphi$$ final state according to previous measurement by BESIII, the resonant parameters of $$phi(1680)$$ are determined to be $$m_{phi(1680)} = (1683 pm 7 pm 9)~{rm MeV}/c^{2}$$ (statistical and systematic errors, respectively), $$Gamma_{phi(1680)} = (149 pm 12 pm 13)~{rm MeV}$$ and, depending on the possible presence of interfering resonances, $$Gamma^{e^{+}e^{-}}_{phi(1680)}cdot {cal B}[phi(1680)toetaphi] = (122 pm 6 pm 13)~{rm eV}$$, $$(219 pm 15 pm 18)~{rm eV}$$, $$(163 pm 11 pm 13)~{rm eV}$$ or $$(203 pm 12 pm 18)~{rm eV}$$. The branching fraction of $$phi(1680)toetaphi$$ decay is determined to be approximately 20%. Additionally, the branching fraction for $$J/psitoetaphi$$ is measured to be $$(7.1pm 1.0 pm 0.5)times 10^{-4}$$. However, there is no significant observed $$phi(2170)$$ signal in the $$etaphi$$ final states in this analysis, and correspondingly the upper limit for $$Gamma^{e^{+}e^{-}}_{phi(2170)}cdot {cal B}(phi(2170)toetaphi)$$ is determined to be either $$0.17~{rm eV}$$ (for two fits), or $$18.6~{rm eV}$$ (remaining two fits), at 90% confidence level.

論文

Nested antiferromagnetic spin fluctuations and non-Fermi-liquid behavior in electron-doped CeCo$$_{1-x}$$Ni$$_{x}$$In$$_5$$

酒井 宏典; 徳永 陽; 神戸 振作; Zhu, J.-X.*; Ronning, F.*; Thompson, J. D.*; 小手川 恒*; 藤 秀樹*; 鈴木 康平*; 大島 佳樹*; et al.

Physical Review B, 106(23), p.235152_1 - 235152_8, 2022/12

https://doi.org/10.1103/PhysRevB.106.235152
 被引用回数：1 パーセンタイル：5.97(Materials Science, Multidisciplinary)

Ni置換系CeCo$$_{1-x}$$Ni$$_x$$In$$_5$$について、核四重極共鳴と核磁気共鳴(NQR/NMR)を用いて調べた。$$T_{rm c}$$=2.3Kの超伝導転移gは、Ni置換によって徐々に下がってゆき、$$x$$=0.25の時にゼロとなる。超格子を用いた密度関数計算によってNQRスペクトルの帰属を行い、スピン格子緩和率$$1/T_1$$が一様に抑えられ、反強磁性スピン揺らぎがNi置換によって弱められることを明らかにした。$$x$$=0.25のとき、$$(T_1T)^{-1}$$が、$$T_{rm g}$$=2Kで極大を示すことがわかった。このことは、遍歴電子の反強磁性スピン揺らぎがネスティングによって打ち消し合っているとして理解できる。

論文

$$beta^-$$ decay of exotic P and S isotopes with neutron number near 28

Tripathi, V.*; Bhattacharya, S.*; Rubino, E.*; Benetti, C.*; Perello, J. F.*; Tabor, S. L.*; Liddick, S. N.*; Bender, P. C.*; Carpenter, M. P.*; Carroll, J. J.*; et al.

Physical Review C, 106(6), p.064314_1 - 064314_14, 2022/12

https://doi.org/10.1103/PhysRevC.106.064314
 被引用回数：5 パーセンタイル：56.72(Physics, Nuclear)

ミシガン州立大学の国立超伝導サイクロトロン研究所にて、中性子過剰なリン、硫黄同位体を生成し、そこからのベータ崩壊半減期および娘核の励起準位を測定した。$$^{42}$$Pの崩壊によって得られるエネルギー準位から、この原子核の基底状態は$$2^-$$あるいは$$3^-$$であることが示唆された。中性子数が偶数の硫黄同位体からの崩壊様式を系統的に調べた結果、中性子数が増えるにつれてガモフテラー遷移強度の大きな準位の励起エネルギーが高くなることがわかった。これは、大規模殻模型計算によって予言されている現象に一致する。

論文

Novel coupled channel framework connecting the quark model and lattice QCD for the near-threshold $$D_s$$ states

Yang, Z.*; Wang, G.-J.*; Wu, J.-J.*; 岡 眞; Zhu, S.-L.*

Physical Review Letters, 128(11), p.112001_1 - 112001_6, 2022/03

https://doi.org/10.1103/PhysRevLett.128.112001
 被引用回数：46 パーセンタイル：96.04(Physics, Multidisciplinary)

閾値近傍のハドロン共鳴を有限サイズの格子QCDのデータを用いて解析する新しい手法を提案し、正パリティの$$D_s$$メソンのスペクトルに応用した。ハミルトニアン有効理論にクォーク模型,クォークペア生成,DK相互作用の情報を入れてベアな状態と散乱状態の結合を取り入れた。4個の$$D_s$$状態のうち、$$0^+$$と$$1^+$$の状態は散乱状態と強く混合する。一方で、$$1^+$$と$$2^+$$はほとんどベアなクォーク模型状態で記述できる。有限格子サイズでのレベル交差が再現されることを示した。

論文

Revisit the isospin violating decays of $$X$$(3872)

Meng, L.*; Wang, G.-J.*; Wang, B.*; Zhu, S.-L.*

Physical Review D, 104(9), p.094003_1 - 094003_8, 2021/11

https://doi.org/10.1103/PhysRevD.104.094003
 被引用回数：29 パーセンタイル：84.87(Astronomy & Astrophysics)

$$X(3872)$$共鳴のアイソスピンを破る崩壊について再解析を行った。その結果$$X(3872)$$の内部構造と崩壊におけるアイソスピンの破れを定量的に結びつける新しい解析方法を提案し、これを適用した。その結果、$$X(3872)$$における中性メソンチャネルの寄与が80%であることがわかった。

論文

Solving the puzzles of the decay of the heaviest known proton-emitting nucleus $$^{185}$$Bi

Doherty, D. T.*; Andreyev, A. N.; Seweryniak, D.*; Woods, P. J.*; Carpenter, M. P.*; Auranen, K.*; Ayangeakaa, A. D.*; Back, B. B.*; Bottoni, S.*; Canete, L.*; et al.

Physical Review Letters, 127(20), p.202501_1 - 202501_6, 2021/11

https://doi.org/10.1103/PhysRevLett.127.202501
 被引用回数：11 パーセンタイル：64.86(Physics, Multidisciplinary)

$$^{185}$$Bi is the heaviest known proton emitting isotope. Its decay had been observed, but the assumed ground-state lifetime ($$sim$$$$60~mu$$s) was incorrect, leading to unexplained hindrance. With two new experiments at Argonne National Laboratory, two states were clearly identified. One is the proton-emitting ground-state (spin 1/2$$^+$$, half-life: 2.8$$^{+2.3}_{-1.0}$$ $$mu$$s), the second is a 58(2) $$mu$$s $$gamma$$-decaying isomer. The new data show the inversion of the ground and isomeric states compared to neighboring Bi isotopes. This is the only known example of a ground-state proton decay to a daughter nucleus ($$^{184}$$Pb) with a major shell closure.

論文

Implications of the $$Z_{cs}$$(3985) and $$Z_{cs}$$(4000) as two different states

Meng, L.*; Wang, B.*; Wang, G.-J.*; Zhu, S.-L.*

Science Bulletin, 66(20), p.2065 - 2071, 2021/10

https://doi.org/10.1016/j.scib.2021.06.026
 被引用回数：28 パーセンタイル：84.09(Multidisciplinary Sciences)

最近発見された2つのテトラクォーク状態$$Z_{cs}$$(3985)と$$Z_{cs}$$(4000)の崩壊を有効理論を用いて調べた結果、崩壊の分岐比からこれらが同じ状態か異なる状態かを判断できることがわかった。

論文

Probing the long-range structure of the $$T^{+}_{cc}$$ with the strong and electromagnetic decays

Meng, L.*; Wang, G.-J.*; Wang, B.*; Zhu, S.-L.*

Physical Review D, 104(5), p.L051502_1 - L051502_8, 2021/09

https://doi.org/10.1103/PhysRevD.104.L051502
 被引用回数：90 パーセンタイル：98.49(Astronomy & Astrophysics)

最近発見された$$T^+_{cc}$$状態の長距離構造をその強い相互作用と電磁相互作用による崩壊の分岐の様子から推定することが可能であることを示した。その結果、$$T_{cc}$$の主成分は$$D^{*+}D^0$$であることがわかった。

論文

Nanoscale heterogeneity induced by nonmagnetic Zn dopants in the quantum critical metal CeCoIn$$_5$$; $$^{115}$$In NQR/NMR and $$^{59}$$Co NMR study

酒井 宏典; 徳永 陽; 神戸 振作; Zhu, J.-X.*; Ronning, F.*; Thompson, J. D.*; Ramakrishna, S. K.*; Reyes, A. P.*; 鈴木 康平*; 大島 佳樹*; et al.

Physical Review B, 104(8), p.085106_1 - 085106_12, 2021/08

https://doi.org/10.1103/PhysRevB.104.085106
 被引用回数：5 パーセンタイル：27.74(Materials Science, Multidisciplinary)

典型的な量子臨界金属であるCeCoIn$$_5$$は、In元素をZn元素で少量置換することで、反強磁性を誘起できることが知られており、7%Zn置換系では、超伝導も共存する。NQRおよびNMRを用いて、微視的に電子状態を調べた結果、反強磁性はZn置換子周辺で起こり、超伝導は置換子から離れた電子状態が核となって起こり、近接効果により、バルク全体に超伝導が拡がる、という不均一性を見出した。Zn置換子周辺にある局所不均一性は、磁場をかけても残存することも見出した。

論文

Higher fully charmed tetraquarks; Radial excitations and $$P$$-wave states

Wang, G.-J.*; Meng, L.*; 岡 眞; Zhu, S.-L.*

Physical Review D, 104(3), p.036016_1 - 036016_15, 2021/08

https://doi.org/10.1103/PhysRevD.104.036016
 被引用回数：37 パーセンタイル：89.85(Astronomy & Astrophysics)

チャームクォーク2個と反クォーク2個の束縛状態であるテトラクォークの動径励起状態と$$P$$波励起状態のスペクトルを、クォーク模型を用いて解析した。クォーク模型は標準的なカラークーロン力と線形閉じ込め力を持つもので、チャーモニウム状態でパラメータを決めた。ダイクォークの基底状態を用いて、カラーが$$bar 3_c 3_c$$と$$6_c bar 6_c$$の状態を取り入れた計算の結果、$$6_c bar 6_c$$状態が低いエネルギーとなることがわかった。$$rho$$モードと$$lambda$$モードの励起状態を調べた結果、最近発見されたX(6900)に相当するエネルギー領域には$$0^{++}$$状態、$$2^{++}$$状態、$$1^{+-}$$状態、および$$2^{-+}$$$$P$$波状態が対応していることが明らかになった。また、エキゾチックな量子数を持つ$$0^{--}$$や$$1^{-+}$$状態は主に$$P$$波の$$eta_c J/psi$$, $$J/psi J/psi$$にそれぞれ崩壊することがわかった。

論文

Mass spectrum and strong decays of tetraquark $$bar c bar s qq$$ states

Wang, G.-J.*; Meng, L.*; Xiao, L.-Y.*; 岡 眞; Zhu, S.-L.*

European Physical Journal C, 81(2), p.188_1 - 188_12, 2021/02

https://doi.org/10.1140/epjc/s10052-021-08978-0
 被引用回数：42 パーセンタイル：91.79(Physics, Particles & Fields)

クォーク模型を用いて、S波の$$bar c bar s qq$$テトラクォーク状態の質量を計算し、さらに$$D^{-(*)}K^{(*)}$$チャネルへの崩壊幅の計算を行った。これらは、最近LHCbで報告されている$$X^0(2900)$$状態の理解につながる。また、対応する$$I=0$$の状態として、$$X(2649)$$を予言した。この状態が実験的に見つかることで、この模型が実証されてインパクトが大きい。

56 件中 1件目～20件目を表示