Using the TRENTo-3D initial condition model coupled with (3+1)-dimensional CLVisc hydrodynamic simulations, we systematically investigate the left-right splitting of elliptic flow ($\Delta v_{2}$) for soft particles in relativistic heavy-ion collisions. Our study reveals that the final distribution characteristics of $\Delta v_{2}$ are primarily depend on the odd flow harmonics and $v_{2}$...
Neutral and charged vector mesons can exhibit sensitivity to isospin-violating phenomena arising from Landau level splitting when a strong magnetic field ($B$) is present in a QCD medium [1]. A possible case involves the neutral $K^{*0}$ ($d\bar{s}$) and the charged $K^{*+}$ ($u\bar{s}$), which are close in mass and share the same isospin, yet their constituent quarks possess different...
The QGP fireball is a temporally fast-evolving and spatially highly nonuniform system. Instantaneously, the spatial temperature gradients are huge and will have significant influence on the spatial distribution of QCD order parameter and its correlations, but related studies are inadequate.
Based on the local equilibrium assumption and the Markov assumption, we will discuss the phase...
Particle correlations are powerful tools for studying quantum chromodynamics in hadron collisions. In heavy-ion collisions, azimuthal angular correlations probe collective phenomena in hot, dense, nuclear media, such as QGP. The LHCb experiment has the ability to study particle correlations in high-energy hadron collisions at forward rapidity, complementing the results from other experiments....
In this talk, I will present the application of machine learning in holographic QCD. By incorporating the equation of state and baryon number susceptibility data, we leverage machine learning techniques to construct a holographic model capable of predicting the location of the critical endpoint (CEP). Furthermore, we enhance the model using Bayesian inference, providing a refined CEP...
Shear and bulk viscosities are two key transport coefficients that characterize the fundamental properties of quark-gluon plasma.They quantify the response of the energy-momentum tensor to shear flow and divergent flow,serving as crucial input parameters for the phenomenological and transport models that interpret experimental data, such as the elliptic flow $v_2$.
$\quad$ However,...
The shape and orientation of colliding nuclei play a crucial role in determining the initial conditions of the quark-gluon plasma (QGP), which influence key observables such as anisotropic and radial flow. In this talk, we present the measurements of $v_n$, $p_{\rm T}$ fluctuation, and $v_n-p_{\rm T}$ correlations in isobar-like $^{238}$U+$^{238}$U and $^{197}$Au+$^{197}$Au collisions at...
To better understand recent predictions on the moat regime of quantum chromodynamics (QCD) matter, this paper extends the previous work within the two-flavor quark-meson (QM) model to the more realistic 2+1 flavor Polyakov-quark-meson (PQM) model. Mainly, two effects are further taken into account: strange quark and confinement coded through Polyakov loop. Model parameters are chosen to...
Understanding the impact of nuclear structure in high-energy nuclear collisions is critical to advancing our knowledge of quark-gluon plasma (QGP) formation. In this study, we investigate the role of nuclear clustering, in particular the alpha-cluster structure in $^{16}\rm{O}$, using anisotropic flow observations from $^{16}\rm{O}+^{16}\rm{O}$ collisions at RHIC energy. Through systematic...
We discuss Dirac fermions under the coexistent rotation and strong magnetic field called the magnetovortical matter. The partition function for this system is constructed based on thermodynamic stability and gauge invariance [1]. We show that the orbital contribution to bulk thermodynamics dominates over the conventional contribution from anomaly-related spin effects found in Ref. [2]. This...
Due to their weak coupling to the strongly interacting matter produced in relativistic heavy-ion collisions, dileptons serve as a sensitive probe of the initial geometry of the colliding nuclei. In this study, we investigate the influence of initial nuclear quadrupole deformation, characterized by the parameter β2, on dilepton production in U+U collisions at √sNN = 193 GeV. The analysis is...
Searching for the QCD critical end point is one of the most important topic. In this work, we present the study of net-proton cumulants and factorial cumulants in Au+Au collisions from the RHIC-STAR Beam Energy Scan Phase-II program. Careful event and track selections, with efficiency and systematic corrections, yield high-precision results across energies, centralities, and kinematic windows....
In relativistic high-energy heavy-ion collisions, the chiral magnetic effect (CME) could produce a charge separation in quark gluon plasma (QGP) and remain in the final hadron system during evolution, observed as the correlator . However, in collisions, the background effect makes a significant contribution. Therefore, we propose to study the contribution of CME to through collisions.
We...
The ALICE collaboration published the first measurement of the skewness and kurtosis of mean pT fluctuations, which can constrain the initial state of ultra-relativistic nuclear collisions. In this paper, we investigate the higher-order mean pT fluctuations using a multiphase transport model for three different collision systems: pp collision at 5.02 TeV, Pb+Pb collision at 5.02 TeV and Xe+Xe...
In this talk, based on the problem and physics-oriented approach, combined with our knowledge of relativistic kinetic theory, we present for the first time the invariant Lie algebra admitted by the relativistic Boltzmann equation, from which the group invariant transformations can be constructed. As the immediate application of this Lie algebra, we demonstrate that in the case of hard sphere...
Quantum Chromodynamics (QCD), the fundamental theory of the strong interaction, governs the behavior of quarks and gluons. Heavy quarks (charm and bottom) hold unique value in strong interaction research: their large masses ensure production is dominantly governed by perturbative QCD, while the formation mechanisms of heavy quarkonium states (e.g., J/ψ) inherently span QCD's perturbative and...
The medium modification of jet substructure in hot and dense nuclear matter has garnered significant interest from the heavy-ion physics community in recent years. Measurements of inclusive jets show an angular narrowing in nucleus-nucleus collisions, while recent CMS results for photon-tagged jets ($\gamma$+jets) suggest evidence of broadening. In this study, we conduct a theoretical analysis...
Within the framework of a Langevin dynamics model for heavy quarks in a hot and dense medium, combined with a sequential coalescence +fragmentation hadronization scenario which let the $D_{\rm s}$ meson produced earlier than the other hadron, we systematically calculate the Pb+Pb yield spectra of $D_s$, $D^0$, and $\Lambda^+_{c}$, the yield ratios $D_s/D^0$ and $\Lambda^+_{c}/D^0$, and their...
We present a comprehensive study of multiplicity distributions in QCD jets at the LHC. Our analysis combines pQCD calculations within the Double Logarithmic Approximation (DLA) and modified DLA (MDLA), together with comparisons to ATLAS data and PYTHIA simulations. We provide the first direct verification of KNO scaling for both quark- and gluon-initiated jets within the DLA framework by...
In this talk, I will introduce our recent work on the productions of charmonium and exotic hadrons in pp collisions at the LHC energies as well as in $e^+e^-$ collisions at the BESIII energy using the PACIAE model.
We present a machine learning–based framework for modeling temperature-dependent non-perturbative quantities in the quark-gluon plasma (QGP), aimed at improving predictions for heavy quarkonia suppression in high-energy nuclear collisions. Deep neural networks are trained on lattice data to extract temperature profiles of the Debye screening mass $m_D(T)$ and the QCD running coupling...
We present a comprehensive investigation of the heavy quarkonium dynamics in the quark-gluon plasma (QGP), including the dissociation caused by dynamical scatterings off the medium partons and the regeneration from the unbound single heavy quarks. The dissociation cross sections and transition rates for both 2->2 leading-order (gluo-dissociation) and 2->3 next-to-leading order (partonic...
Significant progress, particularly in holography, has clarified how rapidly two-point functions hydrodynamize after a quench. Motivated by non-Gaussian observables relevant to the QCD critical-point program, we ask: how do higher-point functions hydrodynamize relative to two-point functions? We propose two conjectures that organize the ordering and scaling of hydrodynamization times across...
Particles associated with the jet will be deflected from their initial direction due to the scatterings with the thermal partons flowing in the QGP fluid. Such deflections lead to an intra-jet asymmetry coupled with flow, which we can use to extract the properties of the QGP medium. This work calculates the intra-jet asymmetry distribution in both transverse and longitudinal directions and...
Event-by-event mean transverse momentum fluctuations (<𝑝T>) serve as a sensitive probe of initial state overlap geometry and energy density fluctuations in relativistic heavy-ion collisions. We present a systematic investigation of <𝑝T> fluctuations in Au+Au collisions at 3.0–19.6 GeV, examining their centrality and energy dependence with the framework of an improved multiphase transport...
Quarkonium production provides a powerful probe of the deconfinement of strongly interacting matter in high-energy heavy-ion collisions. Because the binding potential of heavy quark--antiquark pairs is screened in the quark--gluon plasma (QGP), measurements of quarkonium yields and polarization can reveal the onset and properties of this deconfined medium. For the J/$\psi$ meson, a bound...
The talk presents our preliminary estimates of heavy flavor (HF) quark energy loss during its propagation through the non-equilibrated medium formed in minimum bias proton-proton (p+p) collisions at LHC energies. The study is inspired by the ongoing hot debates on whether tiny droplets of Quark-Gluon Plasma can be created in collisions of small systems. In this work, we assume that the...
In high-energy proton-proton (pp) collisions at the LHC, non-prompt charm hadrons, originating from beauty hadron decays, provide a valuable probe for beauty quark dynamics, particularly at low transverse momentum ($p_T$) where direct beauty measurements are challenging. We employ the A Multi-Phase Transport (AMPT) model in its string-melting mode to simulate these processes in pp collisions...
Particle azimuthal anisotropies inside jets, defined within the momentum plane perpendicular to the jet axis, carry the information of the QCD cascade process for jet formation. In this work, we propose to measure the medium-induced modifications of the elliptic anisotropy inside jets in relativistic heavy-ion collisions to provide novel insight into the jet quenching phenomenon. By simulating...
Jet quenching is studied in a background magnetic field and a finite baryon chemical potential. The production of energetic partons is calculated using the next-to-leading order (NLO) perturbative Quantum Chromodynamics (pQCD) parton model, while the parton energy loss formula is obtained from the AdS/CFT correspondence incorporating the magnetic field and baryon chemical potential effects....
Using the three-dimensional kinetic Ising model with Metropolis algorithm, we calculate the free energy in the whole phase boundary, particularly near the first phase transition line (1st-PTL). The results show that along the 1st-PTL, as the temperature decreases, the energy barrier between the two coexisting phases diverges. This results in more difficulty to reach the equilibrium, i.e.,...
In relativistic heavy-ion collisions, the production of J/$\psi$ serves as an important probe for studying the properties of quark-gluon plasma (QGP). However, interpreting the modi-fication of J/$\psi$ yields is challenging due to the interplay of hot, such as dissociation and regeneration, and cold nuclear matter effects. Measuring J/$\psi$ production across various collision systems and...
One of the central goals of the RHIC Beam Energy Scan is to identify the transition from ordinary hadronic matter to the Quark–Gluon Plasma (QGP). Elliptic flow ($v_2$), which reflects the azimuthal anisotropy of particle emission, serves as a sensitive probe of collectivity and the active degrees of freedom of the medium. Over the past two decades, systematic studies of collectivity across...
We study the hot medium effects in high-multiplicity proton-proton (pp) collisions at 13 TeV via the charmonium probes. The hot medium is described with the hydrodynamic model, while charmonium evolutions in the medium are studied with a time-dependent Schr¨odinger equation. The hot medium dissociation on charmonium is considered with the temperature-dependent complex potential parametrized...
Exploring the QCD phase transition is one of the most important goals in relativistic heavy-ion collisions. The Beam Energy Scan Program at RHIC has revealed a preliminary non-monotonic behavior of net-proton multiplicity fluctuations with increasing collision energy [1], which is consistent with theoretical predictions [2].
However, the quark-gluon plasma created in relativistic heavy-ion...
At leading order in QCD coupling constant, we compute the energy loss per traveling distance of a heavy quark $dE/dz$ from elastic scattering off thermal quarks and gluons at a temperature $T$, including the thermal perturbative description of soft scatterings and a perturbative QCD-based calculation for hard collisions. We re-derive the analytic formula for $dE/dz$ in the high-energy...
We constructed the matrix model under real rotation $\omega$ in a cylinder of radius $R$, with $R \omega<1$ to preserve causality, by using the background field effective theory. Based on this new matrix model, we investigated the confinement/deconfinement phase transition in $SU(3)$ and $SU(2)$ gauge theories. Our results indicate that a phase transition can occur as long as the...
Directed flow $v_1$ has been used to probe early dynamics in high-energy nuclear collisions. The vector meson $\phi(s \overline{s})$, with a mass comparable to that of light baryons, exhibits a small interaction cross section with other hadrons. Therefore, the measurement of $\phi$-meson directed flow $v_1$ provides clean access to the early collision dynamics and the production mechanisms of...
Both ALICE and CMS collaboration report precision measurements of nuclear suppression and collective flow of heavy flavor hadrons at low and intermediate transverse momentum region in PbPb collisions, which drives the theoretical development of the non-perturbative scatterings between heavy quarks and QGP medium. Aim at this, we have improved the LBT model by re-evaluating the heavy quark...
We study the first-order phase transition in holographic QCD models with two-flavor and 2+1-flavor matter at finite temperature and chemical potential. Using the holographic bounce solution, we calculate the key parameters governing phase transition dynamics, including the strength parameter $\alpha$, the inverse duration time $\beta/H_*$, and the bubble wall velocity $v_w$. Along the phase...
Nuclear modifications to parton distribution functions provide an essential baseline for disentangling final-state nuclear matter effects in high-energy nuclear collisions. However, determining the explicit form of the modification factors $r^{\textrm{A}}_i(x,Q^2)$ through global analyses remains challenging, partly due to their complex relationships with observables. In this talk, we...
Fragmentation functions (FFs) are crucial non-perturbative inputs in quantum chromodynamics (QCD) for predicting hadron production cross sections in high-energy scattering processes. In this talk, we present recent progress on global fits of FFs by the Non-perturbative Physics Collaboration (NPC). Our analyses incorporate a comprehensive set of precision measurements, including data from the...
The critical endpoint (CEP) in the quantum chromodynamics (QCD) phase diagram may act as a thermalization point, drawing non-equilibrium systems toward thermodynamic equilibrium. Using transport and gap equations from the NJL model, we show that QCD matter perturbed by velocity fields near the first-order phase transition line evolves toward the CEP. Simulations confirm this attractor...
In this paper, we consider the Einstein-Maxwell-dilaton holographic model for light quarks with nonzero magnetic field and chemical potential. First, we study the phase diagrams in $T-\mu$ and $T-B$ planes. We observe inverse magnetic catalysis which is consistent with the lattice QCD results. We discuss the influence of the magnetic field and chemical potential on the location of the critical...
Strange hadrons have been suggested as sensitive probes for the medium properties of the nuclear matter created in heavy-ion collisions. A dense baryon-rich medium is formed during collisions at center-of-mass energies of a few-GeV. Since strange hadrons are produced near or below the threshold, their phase space distribution and yield ratios may provide strong constraints on the equation of...
We present the first lattice QCD results of quadratic fluctuations and correlations of conserved charges in (2+1)-flavor lattice QCD in the presence of a background magnetic field. The simulations were performed using the Highly Improved Staggered Quarks with physical pion mass $m_\pi$ = 135 MeV on $N_\tau=8$ and 12 lattices. We find that the correlation between net baryon number and electric...
The production of hypertriton has been proposed as an effective method to study the nucleosynthesis mechanism in high-energy hadronic collisions. Within the coalescence picture, the yield of nulcei are sensitive to the interplay between the source size and the spatial distribution of their internal wave function, whereas in the statistical hadronization framework nuclear structure plays little...
The fragmentation process has been proposed as a possible origin of the transverse $\Lambda$ polarization, described by polarizing fragmentation functions (pFFs). In $pp$ collisions, this mechanism can be studied by measuring the $\Lambda$ polarization within jets. We present the first measurement of the transverse polarization of $\Lambda$/$\overline{\Lambda}$ hyperons relative to the jet...
