We construct the QCD equation of state at finite chemical potentials including net baryon, electric charge, and strangeness, based on the conserved charge susceptibilities determined from lattice QCD simulations and the equation of state of the hadron resonance gas model. For the application to relativistic heavy ion collisions we consider the situation of strangeness neutrality and matter with a fixed electric charge-to-baryon ratio, resembling that of heavy nuclei. The importance of finite electric charge and strangeness chemical potentials for particle production in heavy ion collisions is demonstrated using hydrodynamic simulations.
An attempt is made to interpret, in the framework of QCD, the likeness between the shapes of the neutron-neutron strong and electrostatic interactions at the distances $\sim 1÷3$ fm.
We provide a concise review on recent theory advancements towards full-fledged (3+1)D dynamical descriptions of relativistic nuclear collisions at finite baryon density. Heavy-ion collisions at different collision energies produce strongly-coupled matter and probe the QCD phase transition at the crossover, critical point, and first-order phase transition regions. Dynamical frameworks provide a quantitative tool to extract properties of hot QCD matter and map fireballs to the QCD phase diagram. Outstanding challenges are highlighted when confronting current theoretical frameworks with current a…
We review the equation of state of QCD matter at finite densities. We discuss the construction of the equation of state with net baryon number, electric charge, and strangeness using the results of lattice QCD simulations and hadron resonance gas models. Its application to the hydrodynamic analyses of relativistic nuclear collisions suggests that the interplay of multiple conserved charges is important in the quantitative understanding of the dense nuclear matter created at lower beam energies. Several different models of the QCD equation of state are discussed for comparison.
Abstract (abridged edition): Properties of the relativistic nucleon self-energy decomposition of the symmetry energy as well as the equation of state (EOS) of pure neutron matter (PNM) are explored systematically within the QCD sum rules (QCDSR). Our results in the present work have demonstrated that the QCDSR approach can be used to explore the properties of asymmetric nuclear matter (ANM) in a quantitative manner, at least in lower density region. The QCDSR approach establishes a bridge connecting the EOS of ANM and the non-perturbative QCD vacuum, and thus provides a useful way to understan…
We construct the QCD equation of state at finite chemical potentials including net baryon, electric charge, and strangeness based on the results of lattice QCD simulations and the hadron resonance gas model. The situation of strangeness neutrality and a fixed charge-to-baryon ratio, which resembles that of heavy nuclei, is considered for the application to relativistic heavy-ion collisions. This increases the values of baryon chemical potential compared to the case of vanishing strangeness and electric charge chemical potentials, modifying the fireball trajectory in the phase diagram. We perfo…
We have presented a strategy to study nuclei and nuclear matters from first principles, namely, from QCD. We first compute nucleon-nucleon potentials numerically in lattice QCD, and then use them to investigate properties of nuclei and nuclear matter by various methods developed in nuclear physics. As a demonstration that this strategy works, mass and structure of ^4^He, ^16^O and ^40^Ca, and equation of state of nuclear matters are determined with the lattice QCD induced two-nucleon potentials in a heavy quark region as an input. We have found that these nuclei and the symmetric nuclear matte…
Basis Representation for Nuclear Densities from Principal Component Analysis
Fuzhou University（福州大学）；Beihang University（北京航空航天大学）；Università degli Studi di Milano（米兰大学）；INFN, Sezione di Milano（意大利国家核物理研究所米兰分部）；Kyoto University（京都大学）；RIKEN Nishina Center for Accelerator-based Science, RIKEN（理化学研究所筑波加速器科学研究中心）
The nuclear symmetry energy determines the birth of neutron stars and the elementary nucleosynthesis in the universe. To constrain the nuclear symmetry energy, besides the studies in astrophysics, many terrestrial nuclear experiments are being carried out using a wide variety of advanced new facilities. In this paper, by cross-checking two unrelated experimental measurements using the newly updated transport model, we obtained a slightly soft symmetry energy at supra-saturation nuclear densities. While extrapolating to low nuclear densities, this result is compatible with the recent finding by…
The properties of open strange meson $K_1^\pm$ in nuclear matter are estimated in the QCD sum rule approach. We obtain a relation between the in-medium mass and width of $K_1^-$ ($K_1^+$) in nuclear matter, and show that the upper limit of the mass shift is as large as -249 (-35) MeV. The spectral modification of the $K_1$ meson is possible to be probed by using kaon beams at J-PARC. Such measurement together with that of $K^*$ will shed light on how chiral symmetry is partially restored in nuclear matter.
We investigate the medium modification of the generalized vector form factors of the nucleon, which include the electromagnetic and energy-momentum tensor form factors, based on an in-medium modified $π$-$ρ$-$ω$ soliton model. We find that the vector form factors of the nucleon in nuclear matter fall off faster than those in free space, which implies that the charge radii of the nucleon become larger in nuclear medium than in free space. We also compute the corresponding transverse charge densities of the nucleon in nuclear matter, which clearly reveal the increasing of the nucleon size in nuc…
We study single-particle potential of Lambda, Sigma, and Xi hyperons in nucleonic matter starting from the fundamental theory of the strong interaction, QCD. First we carry out a lattice QCD numerical simulation, and extract baryon-baryon interactions from QCD by means of the HAL QCD method. We employ a full QCD gauge configuration ensemble at almost physical point so that we can study the physical world, hence mass of hadrons are nearly physical, for example, pion mass is 146 MeV, kaon mass is 525 MeV, and nucleon mass is 958 MeV. Then, we apply the obtained hyperon interactions to the Brueck…
We propose a new method to determine the spatially or impact-parameter dependent nuclear parton distribution functions (nPDFs) using the double parton scattering (DPS) processes in high-energy heavy-ion (proton-nucleus and nucleus-nucleus) collisions. We derive a simple generic DPS formula in nuclear collisions by accommodating both the nuclear collision geometry and the spatially dependent nuclear modification effect, under the assumption that the impact-parameter dependence of nPDFs is only related to the nuclear thickness function. While the geometric effect is widely adopted, the impact of…
This paper scrutinizes the dynamical QCD effects influence on mesons, namely, the mean-square root radius of a pion in the holographic light-front wave function setup, in the context of the AdS/QCD. The nuclear configurational entropy, associated to mesonic holographic light-front wave functions, is shown to have a critical point that optimizes the two parameters of the spin-improved light-front wave function. The mean-square root pion radius and its cross-section, computed upon these derived values, match the exact existing experimental data to the precision of 0.14\%, below the experimental …
We study the two-color QCD matter within two fundamental quark flavors via both chiral perturbation theory and Nambu--Jona-Lasinio model methods. The effective Lagrangian described by low lying meson and baryon, i.e., diquark, is derived, where the excitations locate in the extended $\mathrm{SU}(4)$ flavor symmetry space. We determine the leading order terms on the dependence of the baryon and axial isospin densities. Then, the two-color NJL model is employed to run the numerical simulation and the phase diagram in the plane of $μ-ν_{5}$ is plotted.
The spin and parity dependent nuclear level densities (NLD) are calculated for medium-heavy nuclei using shell model techniques. The NLD are used to calculate cross sections and reaction rates of interest for nuclear astrophysics and nuclear energy applications. We investigate a new approach of describing the shell model NLD via a constant temperature parametrization. This approach provides new information about the effects of symmetries on the temperature of the low-lying nuclear states, and it is shown to be more versatile for applications.
We report on the application of a cascade + viscous hydro + cascade model for heavy ion collisions in the RHIC Beam Energy Scan range, $\sqrt{s_{\rm NN}}=6.3\dots200$ GeV. By constraining model parameters to reproduce the data we find that the effective(average) value of the shear viscosity over entropy density ratio $η/s$ decreases from 0.2 to 0.08 when collision energy grows from $\sqrt{s_{\rm NN}}\approx7$ to 39 GeV.
With the aim of understanding the phase structure of nuclear matter created in high-energy nuclear collisions at finite baryon density, a beam energy scan program has been carried out at Relativistic Heavy Ion Collider (RHIC). In this mini-review, most recent experimental results on collectivity, criticality and heavy flavor productions will be discussed. The goal here is to establish the connection between current available data and future heavy-ion collision experiments in a high baryon density region.
A unified chiral mean field approach is presented for QCD thermodynamics in a wide range of temperatures and densities. The model simultaneously gives a satisfactory description of lattice QCD thermodynamics and fulfills nuclear matter and astrophysical constraints. The resulting equation of state can be incorporated in relativistic fluid-dynamical simulations of heavy-ion collisions and neutron stars mergers. Access to different regions of the QCD phase diagram can be obtained in simulations of heavy-ion data and observations of neutron star mergers.
The nuclear configurational entropy (NCE) is employed to derive two parameters encoding the Pomeron Regge trajectory and the spectrum of closed strings, which are also related to the glueball mass, precisely matching data of the TOTEM collaboration at the LHC. In the Regge regime of holographic QCD, the (Reggeized) glueball propagator and the gravitational form factor of the proton occupy a relevant spot in AdS/QCD. They are used for deriving the cross-sections for the TeV scale proton-proton scattering process, which are the main ingredient for computing the NCE. The nuclear configurational s…
Over the last decade, numerical solutions of Quantum Chromodynamics (QCD) using the technique of lattice QCD have developed to a point where they are beginning to connect fundamental aspects of nuclear physics to the underlying degrees of freedom of the Standard Model. In this review, the progress of lattice QCD studies of nuclear matrix elements of electroweak currents and beyond-Standard-Model operators is summarized, and connections with effective field theories and nuclear models are outlined. Lattice QCD calculations of nuclear matrix elements can provide guidance for low-energy nuclear r…
