It is shown that when relativistically intense ultrashort laser pulses are reflected from the boundary of a plasma with a near-critical density,the Doppler frequency shift leads to generation of intense radiation in b...It is shown that when relativistically intense ultrashort laser pulses are reflected from the boundary of a plasma with a near-critical density,the Doppler frequency shift leads to generation of intense radiation in both the high-frequency(up to the x-ray)and low-frequency(mid-infrared)ranges.The efficiency of energy conversion into the wavelength range above 3μm can reach several percent,which makes it possible to obtain relativistically intense pulses in the mid-infrared range.These pulses are synchronized with high harmonics in the ultraviolet and x-ray ranges,which opens up opportunities for high-precision pump–probe measurements,in particular,laser-induced electron diffraction and transient absorption spectroscopy.展开更多
The carrier-envelope phase(CEP)φ_(0)is one of the key parameters in the generation of isolated attosecond pulses.In particular,“cosine”pulses(φ_(0)=0)are best suited for generation of single attosecond pulses in a...The carrier-envelope phase(CEP)φ_(0)is one of the key parameters in the generation of isolated attosecond pulses.In particular,“cosine”pulses(φ_(0)=0)are best suited for generation of single attosecond pulses in atomic media.Such“cosine”pulses have the peak of the most intense cycle aligned with the peak of the pulse envelope,and therefore have the highest contrast between the peak intensity and the neighboring cycles.In this paper,the dynamics of single attosecond pulse generation from a relativistically oscillating plasma mirror is investigated.We use an elementary analytical model as well as particle-in-cell simulations to study few-cycle attosecond pulses.We find that the phase of the field driving the surface oscillations depends on the plasma density and preplasma scale length.This leads us to a counterintuitive conclusion:for the case of normal incidence and a sharp plasma-vacuum boundary,the CEP required for the generation of a single attosecond pulse phase is closer toφ_(0)=π/2(a“sine”pulse),with the exact value depending on the plasma parameters.展开更多
This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven second...This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers.展开更多
An accurate and simultaneous ab initio prediction for both light nuclei and nuclear matter has been a longstanding challenge in nuclear physics, due to the significant uncertainties associated with the three-nucleon f...An accurate and simultaneous ab initio prediction for both light nuclei and nuclear matter has been a longstanding challenge in nuclear physics, due to the significant uncertainties associated with the three-nucleon forces.In this Letter, we develop the relativistic quantum Monte Carlo methods for the nuclear ab initio problem, and calculate the ground-state energies of A ≤ 4 nuclei using the two-nucleon Bonn force with an unprecedented high accuracy. The present relativistic results significantly outperform the nonrelativistic results with only twonucleon forces. We demonstrate that both light nuclei and nuclear matter can be well described simultaneously in the relativistic ab initio calculations, even in the absence of three-nucleon forces, and a correlation between the properties of light A ≤ 4 nuclei and the nuclear saturation is revealed. This provides a quantitative understanding of the connection between the light nuclei and nuclear matter saturation properties.展开更多
We propose a compact scheme to modulate a relativistic electron beam(REB)into three-dimensional(3D)nanoscale bunches by injecting a rarefied REB into an underdense plasma.This scheme self-consistently integrates the l...We propose a compact scheme to modulate a relativistic electron beam(REB)into three-dimensional(3D)nanoscale bunches by injecting a rarefied REB into an underdense plasma.This scheme self-consistently integrates the lateral focusing and axial modulation of the REB in its self-driven plasma wakefield.The REB first expels the plasma electrons in its path to form a wake,where the lateral force of the chargeseparation field compresses it to higher density,so that more plasma electrons are expelled as it propagates.The positive feedback loop is repeated until the REB becomes a thin electron filament of density a hundred times that of the original.As it continues to propagate in the elongated electron-free wake bubble,the axial electric field induces an energy chirp on the electron filament,and longitudinally modulates it into 3D nanoscale bunches by asynchronous envelope oscillations.The excitation conditions of this scheme with respect to the beam and plasma parameters,as well as the spatial scale of the obtained electron bunches,are analyzed analytically and agree well with particle-in-cell simulations.In addition,our radiation simulations show that coherent extreme ultraviolet radiation can be generated with such 3D nanoscale bunches.展开更多
We study the Rayleigh-Taylor instability(RTI)of electrostatic plane wave perturbations in compressible relativistic magnetoplasma fluids with thermal ions under gravity in three different cases of when(ⅰ)electrons ar...We study the Rayleigh-Taylor instability(RTI)of electrostatic plane wave perturbations in compressible relativistic magnetoplasma fluids with thermal ions under gravity in three different cases of when(ⅰ)electrons are in isothermal equilibrium,i.e.,classical or nondegenerate,(ⅱ)electrons are fully degenerate(with Te=0),and(ⅲ)electrons are partially degenerate or have finite temperature degeneracy(with Te≠0).While in the cases of(ⅰ)and(ⅲ),we focus on the regimes where the particle's thermal energy is more or less than the rest mass energy,i.e.,βe≡kBTe/mec2<1or>1,the case(ⅱ)considers from weakly to ultra-relativistic degenerate regimes.A general expression of the growth rate of instability is obtained and analyzed in the three different cases relevant to laboratory and astrophysical plasmas,which generalize and advance the previous theory on RTI.展开更多
Based on the Many Worlds Interpretation,I describe reality as a multilayer spacetime,where parallel layers play the role of alternative timelines.I link physics to ethics,arguing that one’s moral choices shape one’s...Based on the Many Worlds Interpretation,I describe reality as a multilayer spacetime,where parallel layers play the role of alternative timelines.I link physics to ethics,arguing that one’s moral choices shape one’s course in the multiverse.I consider one’s ethical decisions as decoherence events,leading to movement between alternative timelines,lighter(higher)or heavier(lower)realities.Sometimes in one’s curvilinear path in spacetime,one can even experience falling toward lower layers,slipping through wormholes.This theory supports free will and the simulation hypothesis.With this background,I explore the idea that a new theory of gravity might open new possibilities to shape matter and change our worldview through the invention of new technology,transforming information into waves and then into solid matter,paving the way for a new Multiverse Aeon for humanity.展开更多
We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and co...We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and coordinate spaces.Our calculation is based on the four-point Green's function rather than the scattering amplitude.Among the sixteen potential components,eight that vanish in the non-relativistic limit are shown to acquire nonzero relativistic and off-shell corrections.In addition to providing relativistic and off-shell corrections to the operator basis commonly used in the literature,we introduce an alternative operator basis that facilitates the derivation of interaction potentials in the coordinate space.Furthermore,we calculate both the long-range and short-range components of the potentials,which can be useful for future experimental analyses at both macroscopic and atomic scales.展开更多
The isospin splitting of the Dirac mass obtained using the relativistic Brueckner-Hartree-Fock(RBHF)theory was thor-oughly investigated.From the perspective in the full Dirac space,the long-standing controversy betwee...The isospin splitting of the Dirac mass obtained using the relativistic Brueckner-Hartree-Fock(RBHF)theory was thor-oughly investigated.From the perspective in the full Dirac space,the long-standing controversy between the momentum-independent approximation(MIA)method and the projection method on the isospin splitting of the Dirac mass in asymmetric nuclear matter was analyzed in detail.We found that the assumption procedure of the MIA method,which assumes that single-particle potentials are momentum independent,is not a sufficient condition that directly leads to the opposite sign of the isospin splitting of the Dirac mass,whereas the extraction procedure of the MIA method,which extracts single-particle potentials from single-particle potential energy,changes the sign.A formal expression of the Dirac mass was obtained by approximately solving a set of equations involved in the extraction procedure.The opposite isospin splitting of the Dirac mass was mainly caused by the extraction procedure,which forcibly assumed that the momentum dependence of the single-particle potential energy was in a quadratic form,in which the strength was solely determined by a constant scalar potential.Improved understanding of the isospin splitting of the Dirac mass from ab initio calculations could enhance our knowledge of neutron-rich systems,such as exotic nuclei and neutron stars.展开更多
We consider a relativistic two-fluid model of superfluidity,in which the superfluid is described by an order parameter that is a complex scalar field satisfying the nonlinear Klein-Gordon equation(NLKG).The coupling t...We consider a relativistic two-fluid model of superfluidity,in which the superfluid is described by an order parameter that is a complex scalar field satisfying the nonlinear Klein-Gordon equation(NLKG).The coupling to the normal fluid is introduced via a covariant current-current interaction,which results in the addition of an effective potential,whose imaginary part describes particle transfer between superfluid and normal fluid.Quantized vorticity arises in a class of singular solutions and the related vortex dynamics is incorporated in the modified NLKG,facilitating numerical analysis which is usually very complicated in the phenomenology of vortex filaments.The dual transformation to a string theory description(Kalb-Ramond)of quantum vorticity,the Magnus force,and the mutual friction between quantized vortices and normal fluid are also studied.展开更多
The sign of higher-order multiplicity fluctuations is a very important parameter for exploring QCD phase transitions.The kurtosis of the net-baryon is typically negative in simulations of the dynamics of the conserved...The sign of higher-order multiplicity fluctuations is a very important parameter for exploring QCD phase transitions.The kurtosis of the net-baryon is typically negative in simulations of the dynamics of the conserved net-baryon density near the QCD critical point.This paper considers the effects of finite size on multiplicity fluctuations with equilibrium critical fluctuations.It is found that the multiplicity fluctuations(or the magnitude of the correlation function D_(ij))are dramatically suppressed with decreasing system size when the size of the system is small compared with the correlation length,which is the so-called acceptance dependence.Consequently,the small correlation function of the small system size results in the magnitude of the negative contribution(~D_(ij)^(4))in the four-point correlation function dominating the positive term(~D_(ij)^(5)),and this finite-size effect induces a dip structure near the QCD critical point.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
This study aims to investigate the production of light nuclei,hypertritons,and Ω-hypernuclei in Pb+Pb collisions at √S_(NN)=5.02TeV TeV using a modified analytical nucleon coalescence model with hyperons.To this end...This study aims to investigate the production of light nuclei,hypertritons,and Ω-hypernuclei in Pb+Pb collisions at √S_(NN)=5.02TeV TeV using a modified analytical nucleon coalescence model with hyperons.To this end,the momentum distributions of two bodies coalescing into dibaryon states and of three bodies coalescing into tribaryon states are derived.Available data on coalescence factors B_(2) and B_(3),transverse momentum spectra,averaged transverse momenta,yield rapidity densities,and yield ratios of the deuteron,antihelium-3,antitriton,and hypertriton measured by the ALICE collaboration are explained.Productions of different species of Ω-hypernuclei H(pΩ^(−)),H(nΩ^(−)),and H(pnΩ^(−))are predicted.Particularly,the production correlations of different light(hyper-)nuclei are studied,and two groups of interesting observables-the averaged transverse momentum ratios of light(hyper-)nuclei to protons(hyperons)and their corresponding yield ratios-are studied.The averaged transverse momentum ratio group exhibits a reverse hierarchy of the nucleus size,and the yield raito group is sensitive to the nucleus production mechanism as well as the size of the nucleus.展开更多
In this work,we consider the collapse of a D-dimensional sphere in the framework of a higher-dimensional spherically symmetric space-time in which the gravitational action chosen is claimed to be somehow linked to the...In this work,we consider the collapse of a D-dimensional sphere in the framework of a higher-dimensional spherically symmetric space-time in which the gravitational action chosen is claimed to be somehow linked to the D-dimensional modified term.This work investigates the criteria for the dynamical instability of anisotropic relativistic sphere systems with D-dimensional modified gravity.The certain conditions are applied that lead to the collapse equation and their effects on adiabatic indexΓin both Newtonian(N)and Post-Newtonian(PN)regimes by using a perturbation scheme.The study explores that theΓplays a crucial role in determining the degree of dynamical instability.This index characterizes the fluid's stiffness and has a significant impact on defining the ranges of instability.This systematic investigation demonstrates the influence of various material properties such as anisotropic pressure,kinematic quantities,mass function,D-dimensional modified gravity parameters,and the radial profile of energy density on the instability of considered structures during their evolution.This work also displays the dynamical behavior of spherically symmetric fluid configuration via graphical approaches.展开更多
This study employs two-dimensional axisymmetric relativistic magnetohydrodynamic simulations to investigate the evolution of supernova remnant(SNR) and pulsar wind nebula(PWN) composite systems in two distinct interst...This study employs two-dimensional axisymmetric relativistic magnetohydrodynamic simulations to investigate the evolution of supernova remnant(SNR) and pulsar wind nebula(PWN) composite systems in two distinct interstellar medium(ISM) configurations: a uniform density distribution and a medium with a sharp density discontinuity. Compared to the uniform density distribution, the ISM with this density discontinuity better reflects the actual conditions and explains the overall morphological characteristics of specific types of SNR-PWN composite systems. These systems exhibit asymmetries, such as an SNR shell with differing radii or an inner PWN located nearer to the shell on one side. The simulation results suggest that the density discontinuity in the ISM is a contributing factor to both the shell asymmetry and the PWN displacement. Specifically, this density variation directly causes the inconsistency in the forward shock speeds of the SNR between high and low density regions, resulting in discrepancies in the shell layer radii. Furthermore, the asymmetric morphology of the PWN and its positional offset emerge through interactions with the reverse shock. The PWN tends to shift toward the SNR shell on one side. The greater the density jump in the background field, the more pronounced the shell radius differences and PWN offset become.展开更多
The study of uranium isotopes plays a crucial role in advancing our knowledge of nuclear physics,particularly in the realm of isospin and exotic nuclei.This study focused on the ground-state properties of uranium isot...The study of uranium isotopes plays a crucial role in advancing our knowledge of nuclear physics,particularly in the realm of isospin and exotic nuclei.This study focused on the ground-state properties of uranium isotopes ranging from A=203 to A=305.The key physical quantities examined included binding energy,quadrupole deformation,isotopic displacement,single-particle energy levels,and nucleon density distributions.Recent experimental advancements in uranium isotope studies have emphasized the indispensable role of theoretical models in interpreting experimental data.Moreover,the industrial applications of uranium—especially in nuclear energy production and weapons development—underscore the importance and necessity of accurate theoretical insights.The framework of the finite-range droplet model(FRDM)was utilized for comparative analysis because its predictions closely align with the experimental results.Through an analysis of the single-particle energy levels and continuous-state occupancy,this study identified 207 U as the proton drip line nucleus.This research not only deepens our understanding of uranium isotopes but also provides a solid theoretical foundation to guide future experimental investigations.展开更多
We present simulation results examining the presence and behavior of standing shocks in zero-energy low angular momentum advective accretion flows and explore their(in)stability properties,taking into account various ...We present simulation results examining the presence and behavior of standing shocks in zero-energy low angular momentum advective accretion flows and explore their(in)stability properties,taking into account various values of specific angular momentum,λ_(0).Within the range 10-50R_(g)(where R_(g)denotes the Schwarzschild radius),shocks are discernible forλ_(0)≥1.75.In the special relativistic hydrodynamic simulation whenλ_(0)=1.80,we find the merger of two shocks resulted in a dramatic increase in luminosity.We present the impact of external and internal flow collisions from the funnel region on luminosity.Notably,oscillatory behavior characterizes shocks within 1.70≤λ_(0)≤1.80.Using free–free emission as a proxy for analysis,we show that the luminosity oscillations between frequencies of 0.1-10 Hz forλ_(0)range as 1.7≤λ_(0)≤1.80.These findings offer insights into quasiperiodic oscillation emissions from certain black hole X-ray binaries,exemplified by GX 339-4.Furthermore,for the supermassive black hole at the Milky Way's center,Sgr A*,oscillation frequencies between 10^(-6)and 10^(-5)Hz were observed.This frequency range,translating to one cycle every few days,aligns with observational data from X-ray telescopes such as Chandra,Swift,and XMM-Newton.展开更多
The simultaneous description for nuclear matter and finite nuclei has been a long-standing challenge in nuclear ab initio theory.With the success for nuclear matter,the relativistic Brueckner-Hartree-Fock(RBHF)theory ...The simultaneous description for nuclear matter and finite nuclei has been a long-standing challenge in nuclear ab initio theory.With the success for nuclear matter,the relativistic Brueckner-Hartree-Fock(RBHF)theory with covariant chiral interactions is a promising ab initio approach to describe both nuclear matter and finite nuclei.In the description of finite nuclei with the current RBHF theory,the covariant chiral interactions have to be localized to make calculations feasible.In order to examine the reliability and validity,in this letter,the RBHF theory with local and nonlocal covariant chiral interactions at leading order is applied to nuclear matter.The low-energy constants in the covariant chiral interactions determined with the local regularization are close to those with the nonlocal regularization.Moreover,the RBHF theory using covariant chiral interactions with local and nonlocal regulators provides an equally good description of the saturation properties of nuclear matter.The present work paves the way for the implementation of covariant chiral interactions in RBHF theory for finite nuclei.展开更多
In this paper,we study the ρ-meson electromagnetic form factors(EMFFs)within the framework of the light-front quark model.The physical form factors G_(C,M,Q)(Q^(2))of the ρ-meson,as well as the charged square radius...In this paper,we study the ρ-meson electromagnetic form factors(EMFFs)within the framework of the light-front quark model.The physical form factors G_(C,M,Q)(Q^(2))of the ρ-meson,as well as the charged square radius<r^(2)>,the magnetic moment μ,and the quadrupole moment Q,are calculated,which describe the behaviors of EMFFs at zero momentum transfer.Using the type-Ⅱ replacement,we find that the zero-mode does contribute zero to the matrix element S_(00)^(+).It is found that the“M→M_(0)”replacement improves the angular condition remarkably,which permits different prescriptions of ρ-meson EMFFs to give the consistent results.The residual tiny violation of angular condition needs other explanations beyond the zero-mode contributions.Our results indicate that the relativistic effects or interaction internal structure are weaken in the zero-binding limit.This work is also applicable to other spin-1 particles.展开更多
We propose a photon-photon collider based on synchrotron gamma sources driven by relativistic electron beams in hollow plasma channels.The collimated(with a divergence angle of~1 mrad)and ultrabrilliant(>10^(28)pho...We propose a photon-photon collider based on synchrotron gamma sources driven by relativistic electron beams in hollow plasma channels.The collimated(with a divergence angle of~1 mrad)and ultrabrilliant(>10^(28)photons s^(-1)·mrad^(-2)·mm^(-2)per 0.1% bandwidth at 0.6 MeV)photon beams are generated by strong electromagnetic fields induced by current filamentation instability,and up to~10^(6) Breit-Wheeler(BW)pairs can be created per shot.Notably,the usage of hollow plasma channels not only enhances synchrotron radiation,but also allows flexible control of the produced photon beams,ensuring the alignment of the two colliding beams and maximizing the two-photon BW process.This setup has the advantage of a clean background by eliminating the yield from the nonlinear BW process,and the signal-to-noise ratio is higher than 10^(2).展开更多
基金supported by the Ministry of Science and Higher Education of the Russian Federation,state assignment for the Lobachevsky University of Nizhny Novgorod,Project No.0729-2020-0035state assignment for the Institute of Applied Physics RAS,Project No.0030-2021-0012.
文摘It is shown that when relativistically intense ultrashort laser pulses are reflected from the boundary of a plasma with a near-critical density,the Doppler frequency shift leads to generation of intense radiation in both the high-frequency(up to the x-ray)and low-frequency(mid-infrared)ranges.The efficiency of energy conversion into the wavelength range above 3μm can reach several percent,which makes it possible to obtain relativistically intense pulses in the mid-infrared range.These pulses are synchronized with high harmonics in the ultraviolet and x-ray ranges,which opens up opportunities for high-precision pump–probe measurements,in particular,laser-induced electron diffraction and transient absorption spectroscopy.
基金This work was supported by the Russian Science Foundation(Grant No.22-22-01031).
文摘The carrier-envelope phase(CEP)φ_(0)is one of the key parameters in the generation of isolated attosecond pulses.In particular,“cosine”pulses(φ_(0)=0)are best suited for generation of single attosecond pulses in atomic media.Such“cosine”pulses have the peak of the most intense cycle aligned with the peak of the pulse envelope,and therefore have the highest contrast between the peak intensity and the neighboring cycles.In this paper,the dynamics of single attosecond pulse generation from a relativistically oscillating plasma mirror is investigated.We use an elementary analytical model as well as particle-in-cell simulations to study few-cycle attosecond pulses.We find that the phase of the field driving the surface oscillations depends on the plasma density and preplasma scale length.This leads us to a counterintuitive conclusion:for the case of normal incidence and a sharp plasma-vacuum boundary,the CEP required for the generation of a single attosecond pulse phase is closer toφ_(0)=π/2(a“sine”pulse),with the exact value depending on the plasma parameters.
基金funding from the European Union’s Horizon 2020 research and innovation program through the European IMPULSE project under Grant Agreement No.871161from LASERLAB-EUROPE V under Grant Agreement No.871124+6 种基金from the Grant Agency of the Czech Republic(Grant No.GM23-05027M)Grant No.PDC2021120933-I00 funded by MCIN/AEI/10.13039/501100011033by the European Union Next Generation EU/PRTRsupported by funding from the Ministerio de Ciencia,Innovación y Universidades in Spain through ICTS Equipment Grant No.EQC2018-005230-Pfrom Grant No.PID2021-125389O A-I00 funded by MCIN/AEI/10.13039/501100011033/FEDER,UEby“ERDF A Way of Making Europe”by the European Unionfrom grants of the Junta de Castilla y León with Grant Nos.CLP263P20 and CLP087U16。
文摘This work demonstrates experimentally the close relation between return currents from relativistic laser-driven target polarization and the quality of the relativistic laser–plasma interaction for laser-driven secondary sources,taking as an example ion acceleration by target normal sheath acceleration.The Pearson linear correlation of maximum return current amplitude and proton spectrum cutoff energy is found to be in the range from~0.70 to 0.94.kA-scale return currents rise in all interaction schemes where targets of any kind are charged by escaping laser-accelerated relativistic electrons.Their precise measurement is demonstrated using an inductive scheme that allows operation at high repetition rates.Thus,return currents can be used as a metrological online tool for the optimization of many laser-driven secondary sources and for diagnosing their stability.In particular,in two parametric studies of laser-driven ion acceleration,we carry out a noninvasive online measurement of return currents in a tape target system irradiated by the 1 PW VEGA-3 laser at Centro de Láseres Pulsados:first the size of the irradiated area is varied at best compression of the laser pulse;second,the pulse duration is varied by means of induced group delay dispersion at best focus.This work paves the way to the development of feedback systems that operate at the high repetition rates of PW-class lasers.
基金supported in part by the National Natural Science Foundation of China (Grant Nos. 12141501, 123B2080, 12435006, 12475117, and 11935003)the National Key Laboratory of Neutron Science and Technology (Grant No. NST202401016)+2 种基金the National Key R&D Program of China (Grant No. 2024YFE0109803)the High-performance Computing Platform of Peking Universitythe funding support from the State Key Laboratory of Nuclear Physics and Technology, Peking University (Grant No. NPT2023ZX03)。
文摘An accurate and simultaneous ab initio prediction for both light nuclei and nuclear matter has been a longstanding challenge in nuclear physics, due to the significant uncertainties associated with the three-nucleon forces.In this Letter, we develop the relativistic quantum Monte Carlo methods for the nuclear ab initio problem, and calculate the ground-state energies of A ≤ 4 nuclei using the two-nucleon Bonn force with an unprecedented high accuracy. The present relativistic results significantly outperform the nonrelativistic results with only twonucleon forces. We demonstrate that both light nuclei and nuclear matter can be well described simultaneously in the relativistic ab initio calculations, even in the absence of three-nucleon forces, and a correlation between the properties of light A ≤ 4 nuclei and the nuclear saturation is revealed. This provides a quantitative understanding of the connection between the light nuclei and nuclear matter saturation properties.
基金supported by the National Key R&D Program of China(Grant No.2024YFA1613400)the National Natural Science Foundation of China(Grant Nos.12475238,12175154,12205201,and 12475248)+5 种基金the Financial Support for Outstanding Talents Training Fund in Shenzhen(Project No.202101)the Shenzhen Science and Technology Program(Grant No.RCYX20221008092851073)the Guangdong Province Key Construction Discipline Scientific Research Capacity Improvement Project(Grant No.2021ZDJS107)the Natural Science Foundation of Guangdong(Grant No.2025A1515012853)the Natural Science Foundation of Top Talent of SZTU(Grant Nos.GDRC202310 and GDRC202423)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2025A1515010791).
文摘We propose a compact scheme to modulate a relativistic electron beam(REB)into three-dimensional(3D)nanoscale bunches by injecting a rarefied REB into an underdense plasma.This scheme self-consistently integrates the lateral focusing and axial modulation of the REB in its self-driven plasma wakefield.The REB first expels the plasma electrons in its path to form a wake,where the lateral force of the chargeseparation field compresses it to higher density,so that more plasma electrons are expelled as it propagates.The positive feedback loop is repeated until the REB becomes a thin electron filament of density a hundred times that of the original.As it continues to propagate in the elongated electron-free wake bubble,the axial electric field induces an energy chirp on the electron filament,and longitudinally modulates it into 3D nanoscale bunches by asynchronous envelope oscillations.The excitation conditions of this scheme with respect to the beam and plasma parameters,as well as the spatial scale of the obtained electron bunches,are analyzed analytically and agree well with particle-in-cell simulations.In addition,our radiation simulations show that coherent extreme ultraviolet radiation can be generated with such 3D nanoscale bunches.
基金support from the University Grants Commission(UGC),Government of India,for a Senior Research Fellowship(SRF)with Ref.No.1161/(CSIR-UGC NET DEC.2018)and 16-6(DEC.2018)/2019(NET/CSIR)。
文摘We study the Rayleigh-Taylor instability(RTI)of electrostatic plane wave perturbations in compressible relativistic magnetoplasma fluids with thermal ions under gravity in three different cases of when(ⅰ)electrons are in isothermal equilibrium,i.e.,classical or nondegenerate,(ⅱ)electrons are fully degenerate(with Te=0),and(ⅲ)electrons are partially degenerate or have finite temperature degeneracy(with Te≠0).While in the cases of(ⅰ)and(ⅲ),we focus on the regimes where the particle's thermal energy is more or less than the rest mass energy,i.e.,βe≡kBTe/mec2<1or>1,the case(ⅱ)considers from weakly to ultra-relativistic degenerate regimes.A general expression of the growth rate of instability is obtained and analyzed in the three different cases relevant to laboratory and astrophysical plasmas,which generalize and advance the previous theory on RTI.
文摘Based on the Many Worlds Interpretation,I describe reality as a multilayer spacetime,where parallel layers play the role of alternative timelines.I link physics to ethics,arguing that one’s moral choices shape one’s course in the multiverse.I consider one’s ethical decisions as decoherence events,leading to movement between alternative timelines,lighter(higher)or heavier(lower)realities.Sometimes in one’s curvilinear path in spacetime,one can even experience falling toward lower layers,slipping through wormholes.This theory supports free will and the simulation hypothesis.With this background,I explore the idea that a new theory of gravity might open new possibilities to shape matter and change our worldview through the invention of new technology,transforming information into waves and then into solid matter,paving the way for a new Multiverse Aeon for humanity.
基金funded in part by the National Natural Science Foundations of China under Grants Nos.12150013,12075058 and 11975090the Science Foundation of Hebei Normal University with Grant No.L2023B09。
文摘We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and coordinate spaces.Our calculation is based on the four-point Green's function rather than the scattering amplitude.Among the sixteen potential components,eight that vanish in the non-relativistic limit are shown to acquire nonzero relativistic and off-shell corrections.In addition to providing relativistic and off-shell corrections to the operator basis commonly used in the literature,we introduce an alternative operator basis that facilitates the derivation of interaction potentials in the coordinate space.Furthermore,we calculate both the long-range and short-range components of the potentials,which can be useful for future experimental analyses at both macroscopic and atomic scales.
基金supported in part by the China Postdoctoral Science Foundation under grant No.2021M700610the National Natural Science Foundation of China(NSFC)(No.12205030)+1 种基金the Fundamental Research Funds for the Central Universities(No.2024CDJXY022)the Institute for Basic Science(No.IBS-R031-D1).
文摘The isospin splitting of the Dirac mass obtained using the relativistic Brueckner-Hartree-Fock(RBHF)theory was thor-oughly investigated.From the perspective in the full Dirac space,the long-standing controversy between the momentum-independent approximation(MIA)method and the projection method on the isospin splitting of the Dirac mass in asymmetric nuclear matter was analyzed in detail.We found that the assumption procedure of the MIA method,which assumes that single-particle potentials are momentum independent,is not a sufficient condition that directly leads to the opposite sign of the isospin splitting of the Dirac mass,whereas the extraction procedure of the MIA method,which extracts single-particle potentials from single-particle potential energy,changes the sign.A formal expression of the Dirac mass was obtained by approximately solving a set of equations involved in the extraction procedure.The opposite isospin splitting of the Dirac mass was mainly caused by the extraction procedure,which forcibly assumed that the momentum dependence of the single-particle potential energy was in a quadratic form,in which the strength was solely determined by a constant scalar potential.Improved understanding of the isospin splitting of the Dirac mass from ab initio calculations could enhance our knowledge of neutron-rich systems,such as exotic nuclei and neutron stars.
文摘We consider a relativistic two-fluid model of superfluidity,in which the superfluid is described by an order parameter that is a complex scalar field satisfying the nonlinear Klein-Gordon equation(NLKG).The coupling to the normal fluid is introduced via a covariant current-current interaction,which results in the addition of an effective potential,whose imaginary part describes particle transfer between superfluid and normal fluid.Quantized vorticity arises in a class of singular solutions and the related vortex dynamics is incorporated in the modified NLKG,facilitating numerical analysis which is usually very complicated in the phenomenology of vortex filaments.The dual transformation to a string theory description(Kalb-Ramond)of quantum vorticity,the Magnus force,and the mutual friction between quantized vortices and normal fluid are also studied.
基金supported by the National Natural Science Foundation of China(No.12305143)the China Postdoctoral Science Foundation(No.2023M731467).
文摘The sign of higher-order multiplicity fluctuations is a very important parameter for exploring QCD phase transitions.The kurtosis of the net-baryon is typically negative in simulations of the dynamics of the conserved net-baryon density near the QCD critical point.This paper considers the effects of finite size on multiplicity fluctuations with equilibrium critical fluctuations.It is found that the multiplicity fluctuations(or the magnitude of the correlation function D_(ij))are dramatically suppressed with decreasing system size when the size of the system is small compared with the correlation length,which is the so-called acceptance dependence.Consequently,the small correlation function of the small system size results in the magnitude of the negative contribution(~D_(ij)^(4))in the four-point correlation function dominating the positive term(~D_(ij)^(5)),and this finite-size effect induces a dip structure near the QCD critical point.
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.
基金supported by the National Natural Science Foundation of China(Nos.12175115 and 12375074).
文摘This study aims to investigate the production of light nuclei,hypertritons,and Ω-hypernuclei in Pb+Pb collisions at √S_(NN)=5.02TeV TeV using a modified analytical nucleon coalescence model with hyperons.To this end,the momentum distributions of two bodies coalescing into dibaryon states and of three bodies coalescing into tribaryon states are derived.Available data on coalescence factors B_(2) and B_(3),transverse momentum spectra,averaged transverse momenta,yield rapidity densities,and yield ratios of the deuteron,antihelium-3,antitriton,and hypertriton measured by the ALICE collaboration are explained.Productions of different species of Ω-hypernuclei H(pΩ^(−)),H(nΩ^(−)),and H(pnΩ^(−))are predicted.Particularly,the production correlations of different light(hyper-)nuclei are studied,and two groups of interesting observables-the averaged transverse momentum ratios of light(hyper-)nuclei to protons(hyperons)and their corresponding yield ratios-are studied.The averaged transverse momentum ratio group exhibits a reverse hierarchy of the nucleus size,and the yield raito group is sensitive to the nucleus production mechanism as well as the size of the nucleus.
基金supported by Researchers Supporting Project number:RSPD2024R650,King Saud University,Riyadh,Saudi Arabia(BA)。
文摘In this work,we consider the collapse of a D-dimensional sphere in the framework of a higher-dimensional spherically symmetric space-time in which the gravitational action chosen is claimed to be somehow linked to the D-dimensional modified term.This work investigates the criteria for the dynamical instability of anisotropic relativistic sphere systems with D-dimensional modified gravity.The certain conditions are applied that lead to the collapse equation and their effects on adiabatic indexΓin both Newtonian(N)and Post-Newtonian(PN)regimes by using a perturbation scheme.The study explores that theΓplays a crucial role in determining the degree of dynamical instability.This index characterizes the fluid's stiffness and has a significant impact on defining the ranges of instability.This systematic investigation demonstrates the influence of various material properties such as anisotropic pressure,kinematic quantities,mass function,D-dimensional modified gravity parameters,and the radial profile of energy density on the instability of considered structures during their evolution.This work also displays the dynamical behavior of spherically symmetric fluid configuration via graphical approaches.
基金supported by the National Natural Science Foundation of China(NSFC,grants No.12393852)the Yunnan Fundamental Research Projects(grant No.202501AS070068)the Program of Graduate Research and Innovation Fund Project of Yunnan University(KC-24249493).
文摘This study employs two-dimensional axisymmetric relativistic magnetohydrodynamic simulations to investigate the evolution of supernova remnant(SNR) and pulsar wind nebula(PWN) composite systems in two distinct interstellar medium(ISM) configurations: a uniform density distribution and a medium with a sharp density discontinuity. Compared to the uniform density distribution, the ISM with this density discontinuity better reflects the actual conditions and explains the overall morphological characteristics of specific types of SNR-PWN composite systems. These systems exhibit asymmetries, such as an SNR shell with differing radii or an inner PWN located nearer to the shell on one side. The simulation results suggest that the density discontinuity in the ISM is a contributing factor to both the shell asymmetry and the PWN displacement. Specifically, this density variation directly causes the inconsistency in the forward shock speeds of the SNR between high and low density regions, resulting in discrepancies in the shell layer radii. Furthermore, the asymmetric morphology of the PWN and its positional offset emerge through interactions with the reverse shock. The PWN tends to shift toward the SNR shell on one side. The greater the density jump in the background field, the more pronounced the shell radius differences and PWN offset become.
基金supported by the National Natural Science Foundation of China(Nos.12175170 and 11675066)。
文摘The study of uranium isotopes plays a crucial role in advancing our knowledge of nuclear physics,particularly in the realm of isospin and exotic nuclei.This study focused on the ground-state properties of uranium isotopes ranging from A=203 to A=305.The key physical quantities examined included binding energy,quadrupole deformation,isotopic displacement,single-particle energy levels,and nucleon density distributions.Recent experimental advancements in uranium isotope studies have emphasized the indispensable role of theoretical models in interpreting experimental data.Moreover,the industrial applications of uranium—especially in nuclear energy production and weapons development—underscore the importance and necessity of accurate theoretical insights.The framework of the finite-range droplet model(FRDM)was utilized for comparative analysis because its predictions closely align with the experimental results.Through an analysis of the single-particle energy levels and continuous-state occupancy,this study identified 207 U as the proton drip line nucleus.This research not only deepens our understanding of uranium isotopes but also provides a solid theoretical foundation to guide future experimental investigations.
基金supported by the National Natural Science Foundation of China(NSFC,Grant No.12073021)。
文摘We present simulation results examining the presence and behavior of standing shocks in zero-energy low angular momentum advective accretion flows and explore their(in)stability properties,taking into account various values of specific angular momentum,λ_(0).Within the range 10-50R_(g)(where R_(g)denotes the Schwarzschild radius),shocks are discernible forλ_(0)≥1.75.In the special relativistic hydrodynamic simulation whenλ_(0)=1.80,we find the merger of two shocks resulted in a dramatic increase in luminosity.We present the impact of external and internal flow collisions from the funnel region on luminosity.Notably,oscillatory behavior characterizes shocks within 1.70≤λ_(0)≤1.80.Using free–free emission as a proxy for analysis,we show that the luminosity oscillations between frequencies of 0.1-10 Hz forλ_(0)range as 1.7≤λ_(0)≤1.80.These findings offer insights into quasiperiodic oscillation emissions from certain black hole X-ray binaries,exemplified by GX 339-4.Furthermore,for the supermassive black hole at the Milky Way's center,Sgr A*,oscillation frequencies between 10^(-6)and 10^(-5)Hz were observed.This frequency range,translating to one cycle every few days,aligns with observational data from X-ray telescopes such as Chandra,Swift,and XMM-Newton.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.12435006,12435007,12475117,12141501,and 123B2080)the National Key R&D Program of China(Grant No.2024YFE0109803)the National Key Laboratory of Neutron Science and Technology(Grant No.NST202401016)。
文摘The simultaneous description for nuclear matter and finite nuclei has been a long-standing challenge in nuclear ab initio theory.With the success for nuclear matter,the relativistic Brueckner-Hartree-Fock(RBHF)theory with covariant chiral interactions is a promising ab initio approach to describe both nuclear matter and finite nuclei.In the description of finite nuclei with the current RBHF theory,the covariant chiral interactions have to be localized to make calculations feasible.In order to examine the reliability and validity,in this letter,the RBHF theory with local and nonlocal covariant chiral interactions at leading order is applied to nuclear matter.The low-energy constants in the covariant chiral interactions determined with the local regularization are close to those with the nonlocal regularization.Moreover,the RBHF theory using covariant chiral interactions with local and nonlocal regulators provides an equally good description of the saturation properties of nuclear matter.The present work paves the way for the implementation of covariant chiral interactions in RBHF theory for finite nuclei.
基金supported by the National Natural Science Foundation of China(Grant Nos.11875122,12175025,and 12147102)Tongling University Talent Program(Grant No.R23100)。
文摘In this paper,we study the ρ-meson electromagnetic form factors(EMFFs)within the framework of the light-front quark model.The physical form factors G_(C,M,Q)(Q^(2))of the ρ-meson,as well as the charged square radius<r^(2)>,the magnetic moment μ,and the quadrupole moment Q,are calculated,which describe the behaviors of EMFFs at zero momentum transfer.Using the type-Ⅱ replacement,we find that the zero-mode does contribute zero to the matrix element S_(00)^(+).It is found that the“M→M_(0)”replacement improves the angular condition remarkably,which permits different prescriptions of ρ-meson EMFFs to give the consistent results.The residual tiny violation of angular condition needs other explanations beyond the zero-mode contributions.Our results indicate that the relativistic effects or interaction internal structure are weaken in the zero-binding limit.This work is also applicable to other spin-1 particles.
基金supported by the Fund of the National Key Laboratory of Plasma Physics(Grant No.6142A04230204)the National Natural Science Foundation of China(Project No.12075046).
文摘We propose a photon-photon collider based on synchrotron gamma sources driven by relativistic electron beams in hollow plasma channels.The collimated(with a divergence angle of~1 mrad)and ultrabrilliant(>10^(28)photons s^(-1)·mrad^(-2)·mm^(-2)per 0.1% bandwidth at 0.6 MeV)photon beams are generated by strong electromagnetic fields induced by current filamentation instability,and up to~10^(6) Breit-Wheeler(BW)pairs can be created per shot.Notably,the usage of hollow plasma channels not only enhances synchrotron radiation,but also allows flexible control of the produced photon beams,ensuring the alignment of the two colliding beams and maximizing the two-photon BW process.This setup has the advantage of a clean background by eliminating the yield from the nonlinear BW process,and the signal-to-noise ratio is higher than 10^(2).
