The search for the chiral magnetic effect(CME) in relativistic heavy-ion collisions(HICs) is challenged by significant background contamination. We present a novel deep learning approach based on a U-Net architecture ...The search for the chiral magnetic effect(CME) in relativistic heavy-ion collisions(HICs) is challenged by significant background contamination. We present a novel deep learning approach based on a U-Net architecture to time-reversely unfold the dynamics of CME-related charge separation, enabling the reconstruction of the physics signal across the entire evolution of HICs. Trained on the events simulated by a multi-phase transport model with different cases of CME settings, our model learns to recover the charge separation based on final-state transverse momentum distributions at either the quark–gloun plasma freeze-out or hadronic freeze-out. This devises a methodological tool for the study of CME and underscores the promise of deep learning approaches in retrieving physics signals in HICs.展开更多
We investigated the chiral magnetic effect(CME)in relativistic heavy-ion collisions through an improved two-plane method analysis of theΔγobservable,probing CP-symmetry breaking in the strong interactions and topolo...We investigated the chiral magnetic effect(CME)in relativistic heavy-ion collisions through an improved two-plane method analysis of theΔγobservable,probing CP-symmetry breaking in the strong interactions and topological properties of the QCD vacuum.Using a multiphase transport model with tunable CME strengths,we systematically compared the Au+Au and isobar collisions at√s_(NN)=200 GeV.We observed a reduced difference in the CME signal-to-background ratio between the spectator and participant planes for Au+Au collisions compared with isobar collisions.A comprehensive chi-square analysis across all three collision systems revealed stronger CME signatures in Au+Au collisions than in isobar collisions,particularly when measured with respect to the spectator plane.Our findings demonstrate the enhanced experimental reliability of the two-plane method for CME detection in Au+Au collisions.展开更多
A study on the effect of applied magnetic field was performed with six types of soils collected fromnortheastern China. Magnetic field was found to cause changes of soil physicc-chemical properties and soilenzyme acti...A study on the effect of applied magnetic field was performed with six types of soils collected fromnortheastern China. Magnetic field was found to cause changes of soil physicc-chemical properties and soilenzyme activities. An appropriate applied magnetic field could cut down soil zeta-potential, soil specificsurface, soil water potential and soil swelling capacity; raise the charge density on soil colloids and theactivities of invertase, hydrogen peroxidase and amylase in the soils; enhance soil aggregation and improvesoil structural status and soil water-releasing capability.展开更多
We study the influence of the chiral phase transition on the chiral magnetic effect. The azimuthal charge-particle correlations as functions of the temperature are calculated. It is found that there is a pronounced cu...We study the influence of the chiral phase transition on the chiral magnetic effect. The azimuthal charge-particle correlations as functions of the temperature are calculated. It is found that there is a pronounced cusp in the correlations as the temperature reaches its critical value for the QCD phase transition. It is predicted that there will be a drastic suppression of the charge-particle correlations as the collision energy in RHIC decreases to below a critical value. We show then the azimuthal charge-particle correlations can be the signal to identify the occurrence of the QCD phase transitions in RHIC energy scan experiments.展开更多
The authors have shown that the process data can be modeled on the basis of chemical thermodynamics. The authors offer general information of the equation in the presence of a magnetic field. As a result, studies have...The authors have shown that the process data can be modeled on the basis of chemical thermodynamics. The authors offer general information of the equation in the presence of a magnetic field. As a result, studies have shown that the magnetic effects strongly influence the thermodynamics of information.展开更多
The authors have shown that the process of information and thinking can be modeled on the basis of chemical thermodynamics. The authors offer general equations to calculate the thinking of the work of judgment the L a...The authors have shown that the process of information and thinking can be modeled on the basis of chemical thermodynamics. The authors offer general equations to calculate the thinking of the work of judgment the L and of entropy solutions G in the presence of a magnetic field. As a result, studies have shown that the magnetic effects strongly influence the thermodynamics of the process of thinking.展开更多
The chiral magnetic effect (CME) refers to a charge separation along a strong magnetic field due to an imbalanced chirality of quarks from interactions with the vacuum topological gluon field. This chiral anomaly is a...The chiral magnetic effect (CME) refers to a charge separation along a strong magnetic field due to an imbalanced chirality of quarks from interactions with the vacuum topological gluon field. This chiral anomaly is a fundamental property of quantum chromodynamics (QCD) and, therefore, an observation of the CME would have far-reaching impact on our understanding of QCD and Nature. The measurements of the CME-sensitive azimuthal correlator Δγ observable in heavy-ion collisions are contaminated by a major background induced by elliptic flow anisotropy. Several novel approaches have been carried out, including a dedicated isobar collision program, to address this flow-induced background. Further background effects, arising from nonflow correlations, have been studied. While the isobar data are consistent with zero CME signal with an upper limit of 10% of the measured Δγ, the Au+Au midcentral data suggest a positive CME signal on the order of 10% of the measured Δγ with a significance of ~2 standard deviations. Future increased statistics and improved detector capability should yield a firm conclusion on the existence (or the lack) of the CME in relativistic heavy-ion collisions.展开更多
Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie te...Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie temperature and instability in air,it is hard to realize practical applications for the reported layered magnetic materials at present.In this paper,we developed a space-confined chemical vapor deposition method to synthesize ultrathin air-stable ε-Fe_(2)O_(3) nanosheets with Curie temperature above 350 K.The ε-Fe_(2)O_(3)/NbSe_(2) heterojunction was constructed to study the magnetic proximity effect on the superconductivity of the NbSe_(2) multilayer.The electrical transport results show that the subtle proximity effect can modulate the interfacial spin–orbit interaction while undegrading the superconducting critical parameters.Our work paves the way to construct 2D heterojunctions with ultrathin nonlayered materials and layered van der Waals(vdW)materials for exploring new physical phenomena.展开更多
The behavior of buoyancy-driven magnetohydrodynamic(MHD)nanofluid flows with temperature-sensitive viscosity plays a pivotal role in high-performance thermal systems such as electronics cooling,nuclear reactors,and me...The behavior of buoyancy-driven magnetohydrodynamic(MHD)nanofluid flows with temperature-sensitive viscosity plays a pivotal role in high-performance thermal systems such as electronics cooling,nuclear reactors,and metallurgical processes.This study focuses on the boundary layer flow of a Casson-based sodium alginate Fe3O4 nanofluid influenced by magnetic field-dependent viscosity and thermal radiation,as it interacts with a vertically stretching sheet under dissipative conditions.To manage the inherent nonlinearities,Lie group transformations are applied to reformulate the governing boundary layer equations into similarity forms.These reduced equations are then solved via the Spectral Quasi-Linearization Method(SQLM),ensuring high accuracy and computational efficiency.The analysis comprehensively explores the impact of key parameters-including mixed convection intensity,magnetic field strength,Casson fluid properties,temperature-dependent viscosity,thermal radiation,and viscous dissipation(Eckert number)-on flow characteristics and heat transfer rates.Findings reveal that increasing magnetic field-dependent viscosity diminishes both skin friction and thermal transport,while buoyancy effects enhance heat transfer but lower shear stress on the surface.This work provides critical insights into controlling heat and momentum transfer in Casson nanofluids,advancing the design of thermal management systems involving complex fluids under magnetic and buoyant forces.展开更多
The construction of carbon nanocoil(CNC)-based chiral-dielectric-magnetic trinity composites is considered as a promising approach to achieve excellent low-frequency microwave absorption.However,it is still challengin...The construction of carbon nanocoil(CNC)-based chiral-dielectric-magnetic trinity composites is considered as a promising approach to achieve excellent low-frequency microwave absorption.However,it is still challenging to further enhance the low frequency microwave absorption and elucidate the related loss mechanisms.Herein,the chiral CNCs are first synthesized on a threedimensional(3D)carbon foam and then combined with the FeNi/NiFe_(2)O_(4) nanoparticles to form a novel chiral-dielectric-magnetic trinity foam.The 3D porous CNC-carbon foam network provides excellent impedance matching and strong conduction loss.The formation of the FeNi-carbon interfaces induces interfacial polarization loss,which is confirmed by the density functional theory calculations.Further permeability analysis and the micromagnetic simulation indicate that the nanoscale chiral magnetic heterostructures achieve magnetic pinning and coupling effects,which enhance the magnetic anisotropy and magnetic loss capability.Owing to the synergistic effect between dielectricity,chirality,and magnetism,the trinity composite foam exhibits excellent microwave absorption performance with an ultrabroad effective absorption bandwidth(EAB)of 14 GHz and a minimum reflection of loss less than-50 dB.More importantly,the C-band EAB of the foam is extended to 4 GHz,achieving the full C-band coverage.This study provides further guidelines for the microstructure design of the chiral-dielectric-magnetic trinity composites to achieve broadband microwave absorption.展开更多
Because of tempting magnetic-dielectric synergies and interfacial effects,designing a simple and low-cost route for producing multidimensional carbon-based magnetic nanocomposites is very important for the development...Because of tempting magnetic-dielectric synergies and interfacial effects,designing a simple and low-cost route for producing multidimensional carbon-based magnetic nanocomposites is very important for the development of microwave absorbers(MAs).In this paper,a facile and propagable Ni-nitrilotriacetic acid chelate(NAC)derived strategy was proposed to selectively fabricate zero-dimensional(0D)/one-dimensional(1D)porous Ni/C magnetic heterostructured nanorods(MHNRs)consisting of 1D carbon nanorod,lots of pores and 0D Ni nanoparticles via a combined hydrothermal and thermally treated methods.The porous Ni/C MHNRs displayed the progressively improved Ni and C crystallinity by controlling the temperature,which resulted in the tunable electromagnetic and microwave absorption properties(MAPs).Additionally,0D/1D porous CoNi/C and Co/C MHNRs could be selectively produced through this strategy by adopting CoNi-NAC and Co-NAC as precursors.Benefiting from desirable interface and magnetic/dielectric synergies,the acquired 0D/1D porous Ni/C,CoNi/C and Co/C MHNRs presented excellent MAPs and certain corrosion resistance properties.In especial,Co/C MHNRs displayed a strong absorption capacity(−47.89 dB),an ultrawide effective absorption bandwidth(8.40 GHz)and small matching thicknesses(∼2 mm),which were a desirable candidate for MAs.Consequently,a facile,low-cost and propagable metal-NAC derived strategy was proposed to synthesize 0D/1D porous carbon-based MHNRs,which presented an alternative technique to develop lightweight efficient MAs.展开更多
Soil enzyme activities as affected by applied magnetic field were studied with three main soils (brown soil, black soil and albic soil) collected from Northeast China. Appropriate intensities of magnetic field could o...Soil enzyme activities as affected by applied magnetic field were studied with three main soils (brown soil, black soil and albic soil) collected from Northeast China. Appropriate intensities of magnetic field could obviously enhance the activities of hydrogen peroxidases, invertases, amylases and phosphatases in the three soils, although the effect varied with types and water regimes of the soils. Increasing times of magnetic treatment could multiple its good effect on the activities of hydrogen peroxidases in soils.展开更多
The magnetic field plays a major role in searching for the chiral magnetic effect in relativistic heavy-ion collisions. If the lifetime of the magnetic field is too short, as predicted by simulations of the field in v...The magnetic field plays a major role in searching for the chiral magnetic effect in relativistic heavy-ion collisions. If the lifetime of the magnetic field is too short, as predicted by simulations of the field in vacuum, the chiral magnetic effect will be largely suppressed. However, the lifetime of the magnetic field will become longer when the QGP medium response is considered. We give an estimate of the effect, especially considering the magnetic field response of the QGP medium, and compare it with the experimental results for the background-subtracted correlator H at RHIC and LHC energies. The results show that our method explains the experimental results better at the top RHIC energy than at the LHC energy.展开更多
Considering the magnetic field response of the QGP medium,we perform a systematical study of the chiral magnetic effect（CME）,and make a comparison with the experimental results for the background-subtracted correlat...Considering the magnetic field response of the QGP medium,we perform a systematical study of the chiral magnetic effect（CME）,and make a comparison with the experimental results for the background-subtracted correlator H at the energies of the RHIC Beam Energy Scan（BES） and the LHC energy.The CME signals from our computations show a centrality trend and beam energy dependence that are qualitatively consistent with the experimental measurements of the charge dependent correlations.The time evolution of the chiral electromagnetic current at the RHIC and LHC energies is systematically studied.The dependence of the time-integrated current signal on the beam energy s1/2with different centralities is investigated.Our phenomenological analysis shows that the time-integrated electromagnetic current is maximal near the collision energy s1/2≈39 GeV.The qualitative trend of the induced electromagnetic current is in agreement with the CME experimental results at the RHIC and LHC energies.展开更多
We propose a novel method to search for the chiral magnetic effect（cme） in heavy ion collisions.We argue that the relative strength of the magnetic field（mainly from spectator protons and responsible for the cme）w...We propose a novel method to search for the chiral magnetic effect（cme） in heavy ion collisions.We argue that the relative strength of the magnetic field（mainly from spectator protons and responsible for the cme）with respect to the reaction plane and the participant plane is opposite to that of the elliptic flow background arising from the fluctuating participant geometry.This opposite behavior in a single collision system,hence with small systematic uncertainties,can be exploited to extract the possible cme signal from the flow background.The method is applied to existing data from rhic,and the outcome discussed.展开更多
The chiral magnetic effect(CME)is a novel transport phenomenon,arising from the interplay between quantum anomalies and strong magnetic fields in chiral systems.In high-energy nuclear collisions,the CME may survive th...The chiral magnetic effect(CME)is a novel transport phenomenon,arising from the interplay between quantum anomalies and strong magnetic fields in chiral systems.In high-energy nuclear collisions,the CME may survive the expansion of the quark-gluon plasma fireball and be detected in experiments.Over the past two decades,experimental searches for the CME have attracted extensive interest at the Relativistic Heavy Ion Collider(RHIC)and the Large Hadron Collider(LHC).The main goal of this study is to investigate three pertinent experimental approaches:the$\gamma$correlator,the R correlator,and the signed balance functions.We exploit simple Monte Carlo simulations and a realistic event generator(EBE-AVFD)to verify the equivalence of the core components among these methods and to ascertain their sensitivities to the CME signal and the background contributions for the isobar collisions at the RHIC.展开更多
In this review, we examine the current theoretical and experimental status of the chiral magnetic effect.We discuss possible future strategies for resolving uncertainties in interpretation including recommendations fo...In this review, we examine the current theoretical and experimental status of the chiral magnetic effect.We discuss possible future strategies for resolving uncertainties in interpretation including recommendations for theoretical work, recommendations for measurements based on data collected in the past five years, and recommendations for beam use in the coming years of RHIC. We specifically investigate the case for colliding nuclear isobars（nuclei with the same mass but different charge） and find the case compelling. We recommend that a program of nuclear isobar collisions to isolate the chiral magnetic effect from background sources be placed as a high priority item in the strategy for completing the RHIC mission.展开更多
We studied the chiral magnetic effect in AuAu,RuRu,and ZrZr collisions at sNN−√=200GeV.The axial charge evolution was modeled with stochastic hydrodynamics,and geometrical quantities were calculated with the Monte Ca...We studied the chiral magnetic effect in AuAu,RuRu,and ZrZr collisions at sNN−√=200GeV.The axial charge evolution was modeled with stochastic hydrodynamics,and geometrical quantities were calculated with the Monte Carlo Glauber model.By adjusting the relaxation time of the magnetic field,we found our results are in good agreement with background subtracted data for AuAu collisions at the same energy.We also made predictions for RuRu and ZrZr collisions.We found a weak centrality dependence on initial chiral imbalance,which implies that the centrality dependence of chiral magnetic effect signals results mainly from the effects of the magnetic field and volume factor.Furthermore,our results show an unexpected dependence on system size.While the AuAu system has larger chiral imbalance and magnetic field,it was observed to have a smaller signal for the chiral magnetic effect due to the larger volume suppression factor.展开更多
The purpose of this paper is to study the long time asymptotic behavior for a nonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove the existence and nonexistence of the non-trivial f...The purpose of this paper is to study the long time asymptotic behavior for a nonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove the existence and nonexistence of the non-trivial free asymptotic solutions. In addition, the decay estimates of the solutions are also obtained.展开更多
The Chiral Magnetic Effect（CME） is a macroscopic manifestation of fundamental chiral anomaly in a many-body system of chiral fermions, and emerges as an anomalous transport current in the fluid dynamics framework. E...The Chiral Magnetic Effect（CME） is a macroscopic manifestation of fundamental chiral anomaly in a many-body system of chiral fermions, and emerges as an anomalous transport current in the fluid dynamics framework. Experimental observation of the CME is of great interest and has been reported in Dirac and Weyl semimetals. Significant efforts have also been made to look for the CME in heavy ion collisions. Critically needed for such a search is the theoretical prediction for the CME signal. In this paper we report a first quantitative modeling framework, Anomalous Viscous Fluid Dynamics（AVFD）, which computes the evolution of fermion currents on top of realistic bulk evolution in heavy ion collisions and simultaneously accounts for both anomalous and normal viscous transport effects. AVFD allows a quantitative understanding of the generation and evolution of CME-induced charge separation during the hydrodynamic stage, as well as its dependence on theoretical ingredients. With reasonable estimates of key parameters, the AVFD simulations provide the first phenomenologically successful explanation of the measured signal in 200 AGe V Au Au collisions.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.12147101 and 12325507)the National Key Research and Development Program of China (Grant No.2022YFA1604900)+4 种基金the Guangdong Major Project of Basic and Applied Basic Research (Grant No.2020B0301030008 for S.G.and G.M.)the CUHK-Shenzhen university development fund (Grant Nos.UDF01003041 and UDF03003041)Shenzhen Peacock Fund (Grant No.2023TC0179 for K.Z.)the RIKEN TRIP initiative (RIKEN Quantum),JSPS KAKENHI (Grant No.25H01560)JST-BOOST (Grant No.JPMJBY24H9 for L.W.)。
文摘The search for the chiral magnetic effect(CME) in relativistic heavy-ion collisions(HICs) is challenged by significant background contamination. We present a novel deep learning approach based on a U-Net architecture to time-reversely unfold the dynamics of CME-related charge separation, enabling the reconstruction of the physics signal across the entire evolution of HICs. Trained on the events simulated by a multi-phase transport model with different cases of CME settings, our model learns to recover the charge separation based on final-state transverse momentum distributions at either the quark–gloun plasma freeze-out or hadronic freeze-out. This devises a methodological tool for the study of CME and underscores the promise of deep learning approaches in retrieving physics signals in HICs.
基金supported by the National Key Research and Development Program of China(No.2022YFA1604900)the National Natural Science Foundation of China(Nos.12147101,12325507,and 12105054)the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030008)。
文摘We investigated the chiral magnetic effect(CME)in relativistic heavy-ion collisions through an improved two-plane method analysis of theΔγobservable,probing CP-symmetry breaking in the strong interactions and topological properties of the QCD vacuum.Using a multiphase transport model with tunable CME strengths,we systematically compared the Au+Au and isobar collisions at√s_(NN)=200 GeV.We observed a reduced difference in the CME signal-to-background ratio between the spectator and participant planes for Au+Au collisions compared with isobar collisions.A comprehensive chi-square analysis across all three collision systems revealed stronger CME signatures in Au+Au collisions than in isobar collisions,particularly when measured with respect to the spectator plane.Our findings demonstrate the enhanced experimental reliability of the two-plane method for CME detection in Au+Au collisions.
文摘A study on the effect of applied magnetic field was performed with six types of soils collected fromnortheastern China. Magnetic field was found to cause changes of soil physicc-chemical properties and soilenzyme activities. An appropriate applied magnetic field could cut down soil zeta-potential, soil specificsurface, soil water potential and soil swelling capacity; raise the charge density on soil colloids and theactivities of invertase, hydrogen peroxidase and amylase in the soils; enhance soil aggregation and improvesoil structural status and soil water-releasing capability.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10425521,10675007,10935001the Major State Basic Research Development Program under Grant No.G2007CB815000the Financial Support from China Postdoctoral Science Foundation No.20090460534
文摘We study the influence of the chiral phase transition on the chiral magnetic effect. The azimuthal charge-particle correlations as functions of the temperature are calculated. It is found that there is a pronounced cusp in the correlations as the temperature reaches its critical value for the QCD phase transition. It is predicted that there will be a drastic suppression of the charge-particle correlations as the collision energy in RHIC decreases to below a critical value. We show then the azimuthal charge-particle correlations can be the signal to identify the occurrence of the QCD phase transitions in RHIC energy scan experiments.
文摘The authors have shown that the process data can be modeled on the basis of chemical thermodynamics. The authors offer general information of the equation in the presence of a magnetic field. As a result, studies have shown that the magnetic effects strongly influence the thermodynamics of information.
文摘The authors have shown that the process of information and thinking can be modeled on the basis of chemical thermodynamics. The authors offer general equations to calculate the thinking of the work of judgment the L and of entropy solutions G in the presence of a magnetic field. As a result, studies have shown that the magnetic effects strongly influence the thermodynamics of the process of thinking.
文摘The chiral magnetic effect (CME) refers to a charge separation along a strong magnetic field due to an imbalanced chirality of quarks from interactions with the vacuum topological gluon field. This chiral anomaly is a fundamental property of quantum chromodynamics (QCD) and, therefore, an observation of the CME would have far-reaching impact on our understanding of QCD and Nature. The measurements of the CME-sensitive azimuthal correlator Δγ observable in heavy-ion collisions are contaminated by a major background induced by elliptic flow anisotropy. Several novel approaches have been carried out, including a dedicated isobar collision program, to address this flow-induced background. Further background effects, arising from nonflow correlations, have been studied. While the isobar data are consistent with zero CME signal with an upper limit of 10% of the measured Δγ, the Au+Au midcentral data suggest a positive CME signal on the order of 10% of the measured Δγ with a significance of ~2 standard deviations. Future increased statistics and improved detector capability should yield a firm conclusion on the existence (or the lack) of the CME in relativistic heavy-ion collisions.
基金The work is supported by the National Key Research and Development Program of China(Grant No.2022YFA1204104)the National Natural Science Foundation of China(Grant No.61888102)the Chinese Academy of Sciences(Grant Nos.ZDBS-SSW-WHC001 and XDB33030100).
文摘Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie temperature and instability in air,it is hard to realize practical applications for the reported layered magnetic materials at present.In this paper,we developed a space-confined chemical vapor deposition method to synthesize ultrathin air-stable ε-Fe_(2)O_(3) nanosheets with Curie temperature above 350 K.The ε-Fe_(2)O_(3)/NbSe_(2) heterojunction was constructed to study the magnetic proximity effect on the superconductivity of the NbSe_(2) multilayer.The electrical transport results show that the subtle proximity effect can modulate the interfacial spin–orbit interaction while undegrading the superconducting critical parameters.Our work paves the way to construct 2D heterojunctions with ultrathin nonlayered materials and layered van der Waals(vdW)materials for exploring new physical phenomena.
文摘The behavior of buoyancy-driven magnetohydrodynamic(MHD)nanofluid flows with temperature-sensitive viscosity plays a pivotal role in high-performance thermal systems such as electronics cooling,nuclear reactors,and metallurgical processes.This study focuses on the boundary layer flow of a Casson-based sodium alginate Fe3O4 nanofluid influenced by magnetic field-dependent viscosity and thermal radiation,as it interacts with a vertically stretching sheet under dissipative conditions.To manage the inherent nonlinearities,Lie group transformations are applied to reformulate the governing boundary layer equations into similarity forms.These reduced equations are then solved via the Spectral Quasi-Linearization Method(SQLM),ensuring high accuracy and computational efficiency.The analysis comprehensively explores the impact of key parameters-including mixed convection intensity,magnetic field strength,Casson fluid properties,temperature-dependent viscosity,thermal radiation,and viscous dissipation(Eckert number)-on flow characteristics and heat transfer rates.Findings reveal that increasing magnetic field-dependent viscosity diminishes both skin friction and thermal transport,while buoyancy effects enhance heat transfer but lower shear stress on the surface.This work provides critical insights into controlling heat and momentum transfer in Casson nanofluids,advancing the design of thermal management systems involving complex fluids under magnetic and buoyant forces.
基金supported by the National Natural Science Foundation of China[Grant Nos.52272288 and 51972039]the China Postdoctoral Science Foundation[No.2021M700658].
文摘The construction of carbon nanocoil(CNC)-based chiral-dielectric-magnetic trinity composites is considered as a promising approach to achieve excellent low-frequency microwave absorption.However,it is still challenging to further enhance the low frequency microwave absorption and elucidate the related loss mechanisms.Herein,the chiral CNCs are first synthesized on a threedimensional(3D)carbon foam and then combined with the FeNi/NiFe_(2)O_(4) nanoparticles to form a novel chiral-dielectric-magnetic trinity foam.The 3D porous CNC-carbon foam network provides excellent impedance matching and strong conduction loss.The formation of the FeNi-carbon interfaces induces interfacial polarization loss,which is confirmed by the density functional theory calculations.Further permeability analysis and the micromagnetic simulation indicate that the nanoscale chiral magnetic heterostructures achieve magnetic pinning and coupling effects,which enhance the magnetic anisotropy and magnetic loss capability.Owing to the synergistic effect between dielectricity,chirality,and magnetism,the trinity composite foam exhibits excellent microwave absorption performance with an ultrabroad effective absorption bandwidth(EAB)of 14 GHz and a minimum reflection of loss less than-50 dB.More importantly,the C-band EAB of the foam is extended to 4 GHz,achieving the full C-band coverage.This study provides further guidelines for the microstructure design of the chiral-dielectric-magnetic trinity composites to achieve broadband microwave absorption.
基金financially supported by the National Natural Science Foundation of China(No.62105076)the Innovation Group of Guizhou University(No.[2024]08)+2 种基金the Platform of Science and Technology and Talent Team Plan of Guizhou Province(No.GCC[2023]007)the Guizhou Provincial Basic Research Program(No.ZK[2021]327)the Fok Ying Tung Education Foundation(No.171095)。
文摘Because of tempting magnetic-dielectric synergies and interfacial effects,designing a simple and low-cost route for producing multidimensional carbon-based magnetic nanocomposites is very important for the development of microwave absorbers(MAs).In this paper,a facile and propagable Ni-nitrilotriacetic acid chelate(NAC)derived strategy was proposed to selectively fabricate zero-dimensional(0D)/one-dimensional(1D)porous Ni/C magnetic heterostructured nanorods(MHNRs)consisting of 1D carbon nanorod,lots of pores and 0D Ni nanoparticles via a combined hydrothermal and thermally treated methods.The porous Ni/C MHNRs displayed the progressively improved Ni and C crystallinity by controlling the temperature,which resulted in the tunable electromagnetic and microwave absorption properties(MAPs).Additionally,0D/1D porous CoNi/C and Co/C MHNRs could be selectively produced through this strategy by adopting CoNi-NAC and Co-NAC as precursors.Benefiting from desirable interface and magnetic/dielectric synergies,the acquired 0D/1D porous Ni/C,CoNi/C and Co/C MHNRs presented excellent MAPs and certain corrosion resistance properties.In especial,Co/C MHNRs displayed a strong absorption capacity(−47.89 dB),an ultrawide effective absorption bandwidth(8.40 GHz)and small matching thicknesses(∼2 mm),which were a desirable candidate for MAs.Consequently,a facile,low-cost and propagable metal-NAC derived strategy was proposed to synthesize 0D/1D porous carbon-based MHNRs,which presented an alternative technique to develop lightweight efficient MAs.
文摘Soil enzyme activities as affected by applied magnetic field were studied with three main soils (brown soil, black soil and albic soil) collected from Northeast China. Appropriate intensities of magnetic field could obviously enhance the activities of hydrogen peroxidases, invertases, amylases and phosphatases in the three soils, although the effect varied with types and water regimes of the soils. Increasing times of magnetic treatment could multiple its good effect on the activities of hydrogen peroxidases in soils.
基金Supported by National Natural Science Foundation of China(11747115,11475068)the CCNU-QLPL Innovation Fund(QLPL2016P01)the Excellent Youth Foundation of Hubei Scientific Committee(2006ABB036)
文摘The magnetic field plays a major role in searching for the chiral magnetic effect in relativistic heavy-ion collisions. If the lifetime of the magnetic field is too short, as predicted by simulations of the field in vacuum, the chiral magnetic effect will be largely suppressed. However, the lifetime of the magnetic field will become longer when the QGP medium response is considered. We give an estimate of the effect, especially considering the magnetic field response of the QGP medium, and compare it with the experimental results for the background-subtracted correlator H at RHIC and LHC energies. The results show that our method explains the experimental results better at the top RHIC energy than at the LHC energy.
基金Supported by National Natural Science Foundation of China(11875178,11475068,11747115)the CCNU-QLPL Innovation Fund(QLPL2016P01) the Excellent Youth Foundation of Hubei Scientific Committee(2006ABB036)
文摘Considering the magnetic field response of the QGP medium,we perform a systematical study of the chiral magnetic effect（CME）,and make a comparison with the experimental results for the background-subtracted correlator H at the energies of the RHIC Beam Energy Scan（BES） and the LHC energy.The CME signals from our computations show a centrality trend and beam energy dependence that are qualitatively consistent with the experimental measurements of the charge dependent correlations.The time evolution of the chiral electromagnetic current at the RHIC and LHC energies is systematically studied.The dependence of the time-integrated current signal on the beam energy s1/2with different centralities is investigated.Our phenomenological analysis shows that the time-integrated electromagnetic current is maximal near the collision energy s1/2≈39 GeV.The qualitative trend of the induced electromagnetic current is in agreement with the CME experimental results at the RHIC and LHC energies.
基金Supported by National Natural Science Foundation of China(11647306,11747312,U1732138,11505056,11605054,11628508)US Department of Energy(DE-SC0012910)
文摘We propose a novel method to search for the chiral magnetic effect（cme） in heavy ion collisions.We argue that the relative strength of the magnetic field（mainly from spectator protons and responsible for the cme）with respect to the reaction plane and the participant plane is opposite to that of the elliptic flow background arising from the fluctuating participant geometry.This opposite behavior in a single collision system,hence with small systematic uncertainties,can be exploited to extract the possible cme signal from the flow background.The method is applied to existing data from rhic,and the outcome discussed.
基金Supported by the US Department of Energy(DE-AC02-98CH10886,DE-FG02-89ER40531,DE-FG02-92ER40713,DE-FG02-88ER40424,DE-SC0012910,DE-SC0013391,DE-SC0020651)the National Natural Science Foundation of China(12025501,11905059,12075085)+6 种基金the Strategic Priority Research Program of Chinese Academy of Science with(XDB34030200)the Fundamental Research Funds for the Central Universities(CCNU19ZN019)the Ministry of Science and Technology(MoST)(2016YFE0104800)the China Scholarship Council(CSC),Join Large-Scale Scientific Facility Funds of NSFC and CAS(U2032110)the U.S.Department of Energy,Office of Science,Office of Nuclear Physics,within the framework of the Beam Energy Scan Theory(BEST)Topical Collaborationthe U.S.National Science Foundation(PHY-1913729)the Natural Sciences and Engineering Research Council of Canada,the Fonds de recherche du Québec-Nature et technologies(FRQNT)through the Programmede Bourses d'ExcellencepourÉtudiantsÉtrangers(PBEEE)。
文摘The chiral magnetic effect(CME)is a novel transport phenomenon,arising from the interplay between quantum anomalies and strong magnetic fields in chiral systems.In high-energy nuclear collisions,the CME may survive the expansion of the quark-gluon plasma fireball and be detected in experiments.Over the past two decades,experimental searches for the CME have attracted extensive interest at the Relativistic Heavy Ion Collider(RHIC)and the Large Hadron Collider(LHC).The main goal of this study is to investigate three pertinent experimental approaches:the$\gamma$correlator,the R correlator,and the signed balance functions.We exploit simple Monte Carlo simulations and a realistic event generator(EBE-AVFD)to verify the equivalence of the core components among these methods and to ascertain their sensitivities to the CME signal and the background contributions for the isobar collisions at the RHIC.
文摘In this review, we examine the current theoretical and experimental status of the chiral magnetic effect.We discuss possible future strategies for resolving uncertainties in interpretation including recommendations for theoretical work, recommendations for measurements based on data collected in the past five years, and recommendations for beam use in the coming years of RHIC. We specifically investigate the case for colliding nuclear isobars（nuclei with the same mass but different charge） and find the case compelling. We recommend that a program of nuclear isobar collisions to isolate the chiral magnetic effect from background sources be placed as a high priority item in the strategy for completing the RHIC mission.
基金Supported by International Program for Ph.D Candidates,Sun Yat-Sen University,the National Science Foundation(PHY-1913729)the National Natural Science Foundation of China(11675274,11735007)the Shang-hai Pujiang Program(19PJ1401400)。
文摘We studied the chiral magnetic effect in AuAu,RuRu,and ZrZr collisions at sNN−√=200GeV.The axial charge evolution was modeled with stochastic hydrodynamics,and geometrical quantities were calculated with the Monte Carlo Glauber model.By adjusting the relaxation time of the magnetic field,we found our results are in good agreement with background subtracted data for AuAu collisions at the same energy.We also made predictions for RuRu and ZrZr collisions.We found a weak centrality dependence on initial chiral imbalance,which implies that the centrality dependence of chiral magnetic effect signals results mainly from the effects of the magnetic field and volume factor.Furthermore,our results show an unexpected dependence on system size.While the AuAu system has larger chiral imbalance and magnetic field,it was observed to have a smaller signal for the chiral magnetic effect due to the larger volume suppression factor.
基金Supported by the National Natural Science Foundation of China.
文摘The purpose of this paper is to study the long time asymptotic behavior for a nonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove the existence and nonexistence of the non-trivial free asymptotic solutions. In addition, the decay estimates of the solutions are also obtained.
基金supported by the U.S.Department of Energy,Office of Science,Office of Nuclear Physics,within the framework of the Beam Energy Scan Theory(BEST)Topical Collaborationsupported in part by the National Science Foundation under Grant No.PHY-1352368(SS and JL)+4 种基金by the National Science Foundation of China under Grant No.11735007(JL)by the U.S.Department of Energy under grant Contract Number No.DE-SC0012704(BNL)/DE-SC0011090(MIT)(YY)the Institute for Nuclear Theory for hospitality during the INT-16-3 Programperformed on IU’s Big Red Ⅱ cluster,supported in part by Lilly Endowment,Inc.(through its support for the Indiana University Pervasive Technology Institute)in part by the Indiana METACyt Initiative
文摘The Chiral Magnetic Effect（CME） is a macroscopic manifestation of fundamental chiral anomaly in a many-body system of chiral fermions, and emerges as an anomalous transport current in the fluid dynamics framework. Experimental observation of the CME is of great interest and has been reported in Dirac and Weyl semimetals. Significant efforts have also been made to look for the CME in heavy ion collisions. Critically needed for such a search is the theoretical prediction for the CME signal. In this paper we report a first quantitative modeling framework, Anomalous Viscous Fluid Dynamics（AVFD）, which computes the evolution of fermion currents on top of realistic bulk evolution in heavy ion collisions and simultaneously accounts for both anomalous and normal viscous transport effects. AVFD allows a quantitative understanding of the generation and evolution of CME-induced charge separation during the hydrodynamic stage, as well as its dependence on theoretical ingredients. With reasonable estimates of key parameters, the AVFD simulations provide the first phenomenologically successful explanation of the measured signal in 200 AGe V Au Au collisions.
