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Statistical Physics in Complex Systems:Challenges and Future Prospects
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作者 Maoxin Liu Hui Li +2 位作者 Fanlong Meng Jie Ren Xiaosong Chen 《Chinese Physics Letters》 2025年第3期1-2,共2页
The 19th century saw significant advancements in thermodynamics and the kinetic theory of gases,with J.C.Maxwell and L.E.Boltzmann playing key roles in the development of statistical physics through their work on the ... The 19th century saw significant advancements in thermodynamics and the kinetic theory of gases,with J.C.Maxwell and L.E.Boltzmann playing key roles in the development of statistical physics through their work on the distribution of single-particle states.At the beginning of the 20th century,J.W.Gibbs established modern equilibrium statistical physics based on the statistical distribution of system microstates and the concept of ensembles.Subsequently,statistical physics expanded into the quantum and nonequilibrium domains. 展开更多
关键词 THERMODYNAMICS expanded GASES
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Reduced-width amplitude in nuclear cluster physics
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作者 De-Ye Tao Bo Zhou 《Nuclear Science and Techniques》 2025年第4期23-44,共22页
As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclea... As a cluster overlap amplitude,the reduced-width amplitude is an important physical quantity for analyzing clustering in the nucleus depending on specified channels and has been calculated and widely applied in nuclear cluster physics.In this review,we briefly revisit the theoretical framework for calculating the reduced-width amplitude,as well as the outlines of cluster models to obtain microscopic or semi-microscopic cluster wave functions.We also introduce the recent progress related to cluster overlap amplitudes,including the implementation of cross-section estimation and extension to three-body clustering analysis.Comprehensive examples are provided to demonstrate the application of the reduced-width amplitude in analyzing clustering structures. 展开更多
关键词 Nuclear clustering Microscopic cluster model Reduced-width amplitude
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In-Flight Heating Process of Cerium Oxide Powders in Radio Frequency Thermal Plasma Considering Thermal Resistance Effect
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作者 Su Yi Liu Ruizhe +3 位作者 Ahmad Hilal Zhao Peng Jin Xingyue Zhu Hailong 《稀有金属材料与工程》 北大核心 2026年第3期581-594,共14页
The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF... The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result. 展开更多
关键词 RF thermal plasma thermal resistance effect heating process Biot number
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Anisotropy of Phase Transformation in Aluminum and Copper under Shock Compression:Atomistic Simulations and Neural Network Model
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作者 Evgenii V.Fomin Ilya A.Bryukhanov +1 位作者 Natalya A.Grachyova Alexander E.Mayer 《Computers, Materials & Continua》 2026年第4期548-577,共30页
It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range ... It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range of crystallographic directions of shock loading has not been revealed.In this work,we calculated the shock Hugoniot for aluminum and copper in different crystallographic directions([100],[110],[111],[112],[102],[114],[123],[134],[221]and[401])of shock compression using molecular dynamics(MD)simulations.The results showed a high pressure(>160 GPa for Cu and>40 GPa for Al)of the FCC-to-BCC transition.In copper,different characteristics of the phase transition are observed depending on the loading direction with the[100]compression direction being the weakest.The FCC-to-BCC transition for copper is in the range of 150–220 GPa,which is consistent with the existing experimental data.Due to the high transition pressure,the BCC phase transition in copper competes with melting.In aluminum,the FCC-to-BCC transition is observed for all studied directions at pressures between 40 and 50 GPa far beyond the melting.In all considered cases we observe the coexistence of HCP and BCC phases during the FCC-to-BCC transition,which is consistent with the experimental data and atomistic calculations;this HCP phase forms in the course of accompanying plastic deformation with dislocation activity in the parent FCC phase.The plasticity incipience is also anisotropic in bothmetals,which is due to the difference in the projections of stress on the slip plane for different orientations of the FCC crystal.MD modeling results demonstrate a strong dependence of the FCC-to-BCC transition on the crystallographic direction,in which the material is loaded in the copper crystals.However,MD simulations data can only be obtained for specific points in the stereographic direction space;therefore,for more comprehensive understanding of the phase transition process,a feed-forward neural network was trained using MD modeling data.The trained machine learning model allowed us to construct continuous stereographic maps of phase transitions as a function of stress in the shock-compressed state of metal.Due to appearance and growth of multiple centers of new phase,the FCC-to-BCC transition leads to formation of a polycrystalline structure from the parent single crystal. 展开更多
关键词 Molecular dynamics(MD) ALUMINUM COPPER shock wave polymorphic phase transformation polycrystalline structure neural network model
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Practical algorithm for simulating thermal pure quantum states
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作者 Wei-Bo He Yun-Tong Yang Hong-Gang Luo 《Chinese Physics B》 2026年第1期170-178,共9页
The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonal... The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonalization or quantum Monte Carlo simulations,particularly at finite temperatures.In this work,we propose a new algorithm for obtaining thermal pure quantum states,which allows efficient computation of both mechanical and thermodynamic properties at finite temperatures.We implement this algorithm in our open-source C++template library,Physica.Combining the improved algorithm with state-of-the-art software engineering,our implementation achieves high performance and numerical stability.As an example,we demonstrate that for the 4×4 Hubbard model,our method runs approximately 10~3times faster than HΦ3.5.2.Moreover,the accessible temperature range is extended down toβ=32 across arbitrary doping levels.These advances significantly push forward the frontiers of benchmarking for quantum many-body systems. 展开更多
关键词 Physica thermal pure quantum states Hubbard model strong correlated electron systems
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Production of ^(287,288)Mc isotopes in the ^(48)Ca+^(243)Am reaction at China Accelerator Facility for Superheavy Elements
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作者 X.Y.Huang Z.Y.Zhang +38 位作者 J.G.Wang L.Ma C.L.Yang M.H.Huang X.L.Wu Z.G.Gan H.B.Yang M.M.Zhang Y.L.Tian Y.S.Wang J.Y.Wang Y.H.Qiang G.Xie S.Y.Xu Z.Zhao Z.C.Li L.C.Sun L.Zhu X.Zhang H.Zhou F.Guan Z.H.Li W.X.Huang Z.Qin Y.Wang X.J.Yin Y.F.Cui Z.W.Lu Y.He L.T.Sun Z.Z.Ren S.G.Zhou V.K.Utyonkov A.A.Voinov Yu.S.Tsyganov A.N.Polyakov D.I.Solovyev N.D.Kovrizhnykh M.V.Shumeiko 《Chinese Physics Letters》 2026年第1期9-16,共8页
We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-... We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-2(SHANS2),a gas-filled recoil separator located at the China Accelerator Facility for Superheavy Elements(CAFE2).In total,20 decay chains are attributed to ^(288)Mc and 1 decay chain is assigned to ^(287)Mc.The measured oa-decay properties of ^(287,288)Mc as well as its descendants are consistent with the known data.No additional decay chains originating from the 2n or 5n reaction channels were detected.The excitation function of the ^(243)Am(^(48)Ca,3n)^(288)Mc reaction was measured at the cross-section level of picobarn,which indicates the promising capability for the study of heavy and superheavy nuclei at the facility. 展开更多
关键词 spectrometer heavy atoms fusionevaporation reaction China Accelerator Facility Superheavy Elements PRODUCTION decay chains ISOTOPES ca am reaction mc
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Simulation on mechanochemical coupling of rotary biomotors F_(1) and V_(1)
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作者 Liqiang Dai Yao-Gen Shu Zhong-Can Ouyang 《Chinese Physics B》 2026年第2期659-667,共9页
The F_(1)-ATPase and V_(1)-ATPase are rotary biomotors.Alignment of their amino acid sequences,which originate from bovine heart mitochondria(1BMF)and Enterococcus hirae(3VR6),respectively,demonstrates that the segmen... The F_(1)-ATPase and V_(1)-ATPase are rotary biomotors.Alignment of their amino acid sequences,which originate from bovine heart mitochondria(1BMF)and Enterococcus hirae(3VR6),respectively,demonstrates that the segment forming the ATP catalytic pocket is highly conserved.Single-molecule experiments,however,have revealed subtle differences in efficiency between the F_(1) and V_(1) motors.Here,we perform both atomistic and coarse-grained molecular dynamics simulations to investigate the mechanochemical coupling and coordination in F_(1) and V_(1) ATPase.Our results show that the correlation between conformational changes in F_(1) is stronger than that in V_(1),indicating that the mechanochemical coupling in F_(1) is tighter than in V_(1).Moreover,the unidirectional rotation of F_(1) is more processive than that of V_(1),which accounts for the higher efficiency observed in F_(1) and explains the occasional backward steps detected in single-molecule experiments on V_(1). 展开更多
关键词 rotary biomotor CORRELATION mechanochemical coupling SIMULATION
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Electric-type Stern-Gerlach effect
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作者 Jiang-Lin Zhou Zou-Chen Fu +1 位作者 Choo Hiap Oh Jing-Ling Chen 《Chinese Physics B》 2026年第1期219-224,共6页
The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Th... The Stern-Gerlach(SG)experiment is a fundamental experiment for revealing the existence of“spin”.In this experiment,beams of silver atoms are sent through inhomogeneous magnetic fields to observe their deflection.Thus,the conventional SG experiment can be viewed as a magnetic-type spin effect.In this work,we successfully generalize the SG effect from magnetic-type to electric-type by solving Dirac's equation with a potential barrier,revealing an extraordinary spin effect.Beams of Dirac particles can be regarded as matter waves.Based on Dirac's equation,we obtain the explicit forms of the incident,reflected,and transmitted waves.The electric-type SG effect shows that the reflected and transmitted waves can exhibit notable spatial shifts,which depend on the spin direction and the incident angle of the wave.The electrictype SG effect has potential applications for separating Dirac particles with different spin directions and for estimating the spin direction of Dirac particles.Some discussions related to the interaction between spin and the electric field are also presented. 展开更多
关键词 Dirac's electron reflection and transmission spin Stern-Gerlach experiment electric-type Stern-Gerlach effect
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Non-Markovian dynamical solver for efficient combinatorial optimization
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作者 Haijie Xu Zhe Yuan 《Chinese Physics B》 2026年第2期583-590,共8页
We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into e... We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into each spin in a history-dependent and trajectory-informed manner,the method effectively suppresses early freezing induced by inelastic boundaries and enhances the system's ability to explore complex energy landscapes.Numerical results on the maximum cut(MAX-CUT)instances of fully connected Sherrington–Kirkpatrick(SK)spin glass models,including the 2000-spin K_(2000)benchmark,demonstrate that the non-Markovian algorithm significantly improves both solution quality and convergence speed.Tests on randomly generated SK instances with 100 to 1000 spins further indicate favorable scalability and substantial gains in computational efficiency.Moreover,the proposed scheme is well suited for massively parallel hardware implementations,such as field-programmable gate arrays,providing a practical and scalable approach for solving large-scale combinatorial optimization problems. 展开更多
关键词 non-Markovian dynamics simulated bifurcation combinatorial optimization maximum cut(MAX-CUT)problem spin glass
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Bayesian neural network evaluation method on the neutron-induced fission product yields of^(232)Th
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作者 Chun-Yuan Qiao Ya-Xuan Wang +2 位作者 Chun-Wang Ma Jun-Chen Pei Yong-Jing Chen 《Nuclear Science and Techniques》 2026年第3期132-142,共11页
Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distribu... Research on neutron-induced fission product yields of^(232)Th is crucial for understanding the competition between symmetric and asymmetric fission in actinide nuclei.However,obtaining complete isotopic yield distributions over a wide range of neutron energies remains a challenge.In this study,a Bayesian neural network model was developed to predict the independent(IND)and cumulative fission yields of^(232)Th under neutron irradiation at various incident energies.To address the limited availability of experimental data for the analysis of IND mass distributions,we substituted mass-number-based yields with the yields of specific isotopes.Furthermore,physical phenomena or quantities,such as the odd-even effect and isospin,were introduced as constraints to enhance the physical consistency of the predictions.The impact of these constraints was evaluated using mass-chain yield distributions and their dependence on energy.Incorporating physical constraints significantly improves the prediction accuracy,yielding more reliable and physically meaningful fission yield data for nuclear physics and reactor design applications. 展开更多
关键词 Bayesian neural network ^(232)Th Independent fission yield Cumulative fission yield Odd–even effect ISOSPIN
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Probing the temperature of the quark soup at trillions of degrees
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作者 Yu-Gang Ma 《Nuclear Science and Techniques》 2026年第3期1-4,共4页
Following over 20 years of research,a direct measurement of the QGP temperature has been achieved at Relativistic Heavy-Ion Collider(RHIC),free from the blue-shift effect and contamination from strong interactions.Thi... Following over 20 years of research,a direct measurement of the QGP temperature has been achieved at Relativistic Heavy-Ion Collider(RHIC),free from the blue-shift effect and contamination from strong interactions.This viewpoint discusses a recent measurement of the QGP temperature at different stages at the Solenoidal Tracker at RHIC(STAR),which used e^(+)e^(-)pairs as penetrating probes. 展开更多
关键词 measurement qgp temperature quark gluon plasma penetrating probes e plus e minus pairs solenoidal tracker TEMPERATURE solenoidal tracker rhic relativistic heavy ion collider
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Femtoscopy reveals how(anti-)deuteron is formed at the LHC
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作者 Kai-Jia Sun 《Nuclear Science and Techniques》 2026年第4期1-4,共4页
The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in... The production of light(anti-)nuclei in high-energy collisions has long posed an apparent paradox:How can loosely bound systems such as the anti-deuteron with a binding energy of only 2.23 MeV be formed and survive in the extreme hot and dense hadronic environment emerging from proton–proton(pp)and heavy-ion collisions,where characteristic thermal energies exceed 100 MeV?A new femtoscopy analysis published on Nature[1]by the ALICE Collaboration at the Large Hadron Collider(LHC)delivers the clearest answer to date. 展开更多
关键词 high energy collisions loosely bound systems alice collaboration anti deuteron LHC femtoscopy analysis hadronic environment FEMTOSCOPY
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Double Wilczek–Zee connection and mixed-state quantum geometric tensor
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作者 Xiaoguang Wang Xiao-Ming Lu +2 位作者 Jing Liu Wenkui Ding Libin Fu 《Chinese Physics B》 2026年第2期300-305,共6页
The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor... The Wilczek–Zee connection(WZC)is a key concept in the study of topology of quantum systems.Here,we introduce the double Wilczek–Zee connection(DWZC)which naturally appears in the pure-state quantum geometric tensor(QGT),another important concept in the field of quantum geometry.The DWZC is Hermitian with respect to the two integer indices,just like the original Hermitian WZC.Based on the symmetric logarithmic derivative operator,we propose a mixed-state quantum geometric tensor.Using the symmetric properties of the DWZC,we find that the real part of the QGT is connected to the real part of the DWZC and the square of eigenvalue differences of the density matrix,whereas the imaginary part can be given in terms of the imaginary part of the DWZC and the cube of the eigenvalue differences.For density matrices with full rank or no full rank,the QGT can be given in terms of real and imaginary parts of the DWZC. 展开更多
关键词 quantum geometry Wilczek–Zee connection quantum geometric tensor
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Enhancing the performance of quantum battery by squeezing reservoir engineering
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作者 Yue Li Rong-Fang Liu +2 位作者 Jia-Bin You Wan-Li Yang Hua Guan 《Chinese Physics B》 2026年第1期226-233,共8页
Reservoir engineering has been widely used in various quantum technologies.Based on a cavity-QED(quantum electrodynamics)model,we propose a potentially practical scheme using squeezed-vacuum reservoir engineering to o... Reservoir engineering has been widely used in various quantum technologies.Based on a cavity-QED(quantum electrodynamics)model,we propose a potentially practical scheme using squeezed-vacuum reservoir engineering to optimize the performance of a quantum battery(QB)located inside a cavity driven by a broadband squeezed laser,which acts as a squeezed-vacuum reservoir.Using the reduced master equation of the QB obtained via the adiabatic elimination method,we focus on the QB's charging dynamics under tunable squeezed reservoirs governed by parametrically controlled squeezing parameters,which dictate the efficiency of energy transfer and the extractable work(ergotropy)of the QB.We show that increasing the squeezing strength improves the charging rate and enables rapid energy transfer,whereas the steady-state energy of the QB saturates at specific values of the squeezing parameter.Notably,the ergotropy of the QB reaches its maximum at a critical squeezing strength and does not scale monotonically with the squeezing strength.This nonmonotonic behavior underscores the existence of optimal parameter regimes,through which the performance of the QB can be significantly enhanced. 展开更多
关键词 quantum computation cavity quantum electrodynamics
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Metallic WO_(2)-Promoted CoWO_(4)/WO_(2) Heterojunction with Intercalation-Mediated Catalysis for Lithium-Sulfur Batteries
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作者 Chan Wang Pengfei Zhang +8 位作者 Jiatong Li Rui Wang Changheng Yang Fushuai Yu Xuening Zhao Kaichen Zhao Xiaoyan Zheng Huigang Zhang Tao Yang 《Nano-Micro Letters》 2026年第1期154-170,共17页
Lithium-sulfur(Li-S)batteries require efficient catalysts to accelerate polysulfide conversion and mitigate the shuttle effect.However,the rational design of catalysts remains challenging due to the lack of a systemat... Lithium-sulfur(Li-S)batteries require efficient catalysts to accelerate polysulfide conversion and mitigate the shuttle effect.However,the rational design of catalysts remains challenging due to the lack of a systematic strategy that rationally optimizes electronic structures and mesoscale transport properties.In this work,we propose an autogenously transformed CoWO_(4)/WO_(2) heterojunction catalyst,integrating a strong polysulfide-adsorbing intercalation catalyst with a metallic-phase promoter for enhanced activity.CoWO_(4) effectively captures polysulfides,while the CoWO_(4)/WO_(2) interface facilitates their S-S bond activation on heterogenous catalytic sites.Benefiting from its directional intercalation channels,CoWO_(4) not only serves as a dynamic Li-ion reservoir but also provides continuous and direct pathways for rapid Li-ion transport.Such synergistic interactions across the heterojunction interfaces enhance the catalytic activity of the composite.As a result,the CoWO_(4)/WO_(2) heterostructure demonstrates significantly enhanced catalytic performance,delivering a high capacity of 1262 mAh g^(−1) at 0.1 C.Furthermore,its rate capability and high sulfur loading performance are markedly improved,surpassing the limitations of its single-component counterparts.This study provides new insights into the catalytic mechanisms governing Li-S chemistry and offers a promising strategy for the rational design of high-performance Li-S battery catalysts. 展开更多
关键词 Lithium sulfur batteries Catalysis Shuttle effect HETEROJUNCTION
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Theoretical study on fusion dynamics and evaporation residue cross sections for superheavy elements 被引量:2
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作者 WANG Nan ZHAO Enguang ZHOU Shangui 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第5期107-112,共6页
The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical pot... The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical potential energy surface.The intrinsic energy and the maximum dynamical deformations for48Ca+248Cm are calculated.The effect of dynamical deformation on the potential energy surface and fusion is investigated.It is found that the dynamical deformation influences the potential energy surface and fusion probability significantly.The dependence of the fusion probability on the angular momentum is investigated.The ER cross sections for some superheavy nuclei in48Ca induced reactions are calculated and it is found that the theoretical results are in good agreement with the experimental results. 展开更多
关键词 蒸发残渣 超重元素 截面 聚变动力 超重核合成 计算结果 动态变形 势能面
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High-energy nuclear physics meets machine learning 被引量:18
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作者 Wan-Bing He Yu-Gang Ma +2 位作者 Long-Gang Pang Hui-Chao Song Kai Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期9-41,共33页
Although seemingly disparate,high-energy nuclear physics(HENP)and machine learning(ML)have begun to merge in the last few years,yielding interesting results.It is worthy to raise the profile of utilizing this novel mi... Although seemingly disparate,high-energy nuclear physics(HENP)and machine learning(ML)have begun to merge in the last few years,yielding interesting results.It is worthy to raise the profile of utilizing this novel mindset from ML in HENP,to help interested readers see the breadth of activities around this intersection.The aim of this mini-review is to inform the community of the current status and present an overview of the application of ML to HENP.From different aspects and using examples,we examine how scientific questions involving HENP can be answered using ML. 展开更多
关键词 Heavy-ion collisions Machine learning Initial state Bulk properties Medium effects Hard probes OBSERVABLES
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Statistical physics of hard combinatorial optimization:Vertex cover problem 被引量:1
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作者 赵金华 周海军 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期114-120,共7页
Typical-case computation complexity is a research topic at the boundary of computer science, applied mathematics, and statistical physics. In the last twenty years, the replica-symmetry-breaking mean field theory of s... Typical-case computation complexity is a research topic at the boundary of computer science, applied mathematics, and statistical physics. In the last twenty years, the replica-symmetry-breaking mean field theory of spin glasses and the associated message-passing algorithms have greatly deepened our understanding of typical-case computation complexity. In this paper, we use the vertex cover problem, a basic nondeterministic-polynomi'al (NP)-complete combinatorial opti- mization problem of wide application, as an example to introduce the statistical physical methods and algorithms. We do not go into the technical details but emphasize mainly the intuitive physical meanings of the message-passing equations. A nonfamiliar reader shall be able to understand to a large extent the physics behind the mean field approaches and to adjust the mean field methods in solving other optimization problems. 展开更多
关键词 spin glass energy minimization replica symmetry breaking belief propagation
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Steady state equilibrium condition of npe~± gas and its application to astrophysics 被引量:1
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作者 Men-Quan Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第1期91-102,共12页
The steady equilibrium conditions for a mixed gas of neutrons, protons, electrons, positrons and radiation fields (abbreviated as npe^± gas) with or without external neutrino flux are investigated, and a genera... The steady equilibrium conditions for a mixed gas of neutrons, protons, electrons, positrons and radiation fields (abbreviated as npe^± gas) with or without external neutrino flux are investigated, and a general chemical potential equilibrium equation μn = μp + Cμe is obtained to describe the steady equilibrium at high temperatures (T 〉 10^9 K). An analytic fitting formula of coefficient C is presented for the sake of simplicity, when neutrinos and antineutrinos are transparent. It is a simple method to estimate the electron fraction for the steady equilibrium npe^± gas that adopts the corresponding equilibrium condition. As an example, we apply this method to the GRB accretion disk and confirm that the composition in the inner region is approximately in equilibrium when the accretion rate is low. For the case with external neutrino flux, we calculate the initial electron fraction of neutrino-driven wind from the proto-neutron star model M15-l1-r1. The results show that the improved equilibrium condition makes the electron fraction decrease significantly more than the case μn = μp + μe when the time is less than 5s post bounce, which may be useful for r-process nucleosynthesis models. 展开更多
关键词 nuclear reactions -- nucleosynthesis weak-interaction GRB accretion disk -- neutrino-driven wind
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Benford's Law in Nuclear Structure Physics 被引量:1
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作者 JIANG Hui SHEN Jia-Jie ZHAO Yu-Min 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第3期43-46,共4页
We investigate Benford's law based on the 2003 version of atomic mass evaluation.It is demonstrated that the first non-zero digit distribution functions for a number of experimental quantities are in reasonable ag... We investigate Benford's law based on the 2003 version of atomic mass evaluation.It is demonstrated that the first non-zero digit distribution functions for a number of experimental quantities are in reasonable agreement with those predicted by Benford's law.The data that we investigate here include 3001 sets of Sp,3060 sets of Sn,2943 sets of two-neutron separation energies S_(2n),2826 sets of two-proton separation energies S_(2p),1643 sets ofβ^(+)-decay energies Q(β^(+)),1243 sets ofβ^(-)-decay energies Q(β^(-)),2595 sets of double,β^(-)-decay energies Q(ββ^(-)),and 2711 sets of energies in electron-capture proton processes Q(εp).The first non-zero digits of these data favor the smaller ones in a logarithmic pattern. 展开更多
关键词 DECAY SEPARATION DIGIT
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