Conveners
分会3：高能重离子物理
- Chair1：张本威 (Central China Normal University)
- Chair2：徐庆华 (Shandong University)
分会3：高能重离子物理
- Chair2：杨帅 (South China Normal University)
- Chair1：王群 (University of Science and Technology of China)
分会3：高能重离子物理
- Chair2：刘峰 (Central China Normal University)
- Chair1：罗晓峰 (Central China Normal University)
分会3：高能重离子物理
- Chair1：侯德富 (CCNU)
- Chair2：周代翠 (Central China Normal University)
高能宇宙线核子与大气分子碰撞，形成广延大气簇射过程，大气簇射的末态粒子可以提供核-核碰撞的强作用过程的关键信息。我国高山宇宙线观测站LHAASO，可以在甚高能宇宙线大气簇射发展最大处，精确测量大气簇射产生的电磁粒子和缪子，为研究核-核碰撞的强作用过程提供了可能。本报告将基于LHAASO实验的数据，研究大气簇射次级粒子中缪子丰度和涨落、缪子的横向分布行为，并通过簇射缪子丰度随天顶角的变化，研究簇射缪子丰度的衰减行为；通过与不同强作用模型的模拟结果进行比较，对强作用模型进行检验；我们还将展示利用大气簇射进行夸克胶子等离子体研究的可行性的初步结果。
Medium modification of jet substructure in the 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...
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...
In the search for the conjectured QCD critical point, higher-order cumulants of conserved quantities have been proposed as sensitive observables and have been studied extensively, both experimentally and theoretically. Recently, a precision measurement [1] of net-proton number fluctuations by the STAR Collaboration was published, focusing on high-statistics Au+Au collision datasets at...
We will investigate the Spin Alignment and Phase Structure of Thermal QGP under Rotation, and the Anomalous Magnetic Moment and Phase Transition of the Magnetized
QCD Background with the finite temperature field theory; and we also study the rotation effect on the deconfinement phase transition in Holographic QCD. And then we make summary and conclusions.
In this talk, we will present our recent results on the QCD matter. We construct a hybrid equation of state (EoS) by smoothly interpolating the EoS in the hadron resonance gas at low temperatures to that in the ideal parton gas at high temperatures, and employ it to study the properties of the quantum chromodynamics (QCD) matter at a finite magnetic field and nonzero chemical potential. We...
Hadronization, the dynamical realization of color confinement in QCD, is the central process connecting the quark-gluon plasma (QGP) produced in relativistic heavy-ion collisions to the hadronic observables measured in detectors. Yet it remains beyond the reach of existing first-principles frameworks, as semi-classical generators lose quantum coherence while lattice QCD cannot access real-time...
Understanding how quarks and gluons evolve and lose energy as they traverse a colored medium is central to interpreting jet observables in high-energy nuclear collisions. We investigate this using a non-perturbative light-front Hamiltonian approach, where the physical quark — dressed by its gluon cloud — is treated as the eigenstate of the vacuum QCD Hamiltonian, and its real-time quantum...
The production of beauty hadrons in proton-proton (pp), proton-lead (p-Pb), and lead-lead (Pb-Pb) collisions offers critical insights into heavy-flavor hadrons production mechanisms across different collision systems. This work presents Bayesian unfolding data-driven measurements of the open beauty hadron production, utilizing ALICE and LHCb data to recover full kinematic information from the...
We present a theoretical study of global and azimuthal-angle-dependent $\Lambda$ hyperon polarization in isobaric $^{96}_{40}$Zr+$^{96}_{40}$Zr collisions at $\sqrt{s_{NN}}=200$ GeV using the TRENTo-3D initial condition model coupled to (3+1)-D viscous hydrodynamic model CLVisc. A longitudinal flow velocity gradient, controlled by $f_v$, is introduced into \trento\ for the first time,...
We present an upgraded formula for Wigner function and spin polarization of fermions emitted by a relativistic fluid at local thermodynamic equilibrium at the freeze-out which improves the one obtained in literatures and used in numerical simulations of relativistic nuclear collisions. By using a new expansion method applicable to freeze-out hypersurfaces with arbitrary geometry, we reproduce...
Entanglement generated in the early stage of relativistic heavy-ion collisions (HIC) is considered a direct and fundamental source for understanding fast thermalization, entropy production, and evolution. Spin entanglement in QCD, arising from non-commutative geometric effects of quantum fields, provides a new avenue to explore the quantum informational footprint of the QCD topological vacuum...
The spin polarization of Lambda hyperon in low-energy Au-Au collision can be generated from the nonlocal nucleon-nucleon scattering. The Lagrangian of baryon-meson interaction is obtained from the chiral perturbation theory, and we introduce a wave packet for the incoming nucleons to describe the nonlocal collision. We evaluate the spin dependent cross section with the approximations that the...
The spin correlation of back-to-back dihadrons emerges in unpolarized high-energy collisions, empowering unpolarized experiments to shed light on spin-dependent fragmentation functions. Transverse spin correlations of partonic $q\bar{q}$ pair manifest through dihadrons, providing a novel probe for the chiral-odd fragmentation function $H_{1T}(z)$. However, although produced gluon also exhibit...
We investigate the nonlinear response of flow harmonics v2, v4 to initial-state eccentricities ϵ2, ϵ4 within the Gubser-flow framework. By extending the perturbative solutions of Gubser flow, we derive analytic nonlinear response relations connecting the eccentricities ϵ2, ϵ4 to the flow harmonics v2, v4. Our results reproduce the well-known result v4/v2^2 → 1/2 in large transverse momentum pT...
The initial-state geometry in relativistic heavy-ion collisions provides a novel probe to nuclear cluster structure. For 20Ne, a novel approach is proposed to distinguish between the cluster configurations (5α versus α+16O) in order to gain insight into nuclear structure transitions governed by many-body quantum correlations. Through analytical calculations with the microscopic Brink model and...
Inspired by Belle data of $\Lambda$ polarization, the polarized transverse-momentum-dependent fragmentation function (TMD FF) $D_{1T}^\perp$ become a hotspot in both theory and experiments. Several parametrizations of $D_{1T}^\perp$ has been proposed with different assumptions on their flavor dependences. Employing an isospin symmetric framework we studied transverse polarizations of $\Lambda$...
High-energy small system collisions exhibit remarkable flow-like signatures, but separating soft multiple-parton interactions from hard jet fragmentation in the development of collective behavior remains a critical challenge. This talk presents a unified framework leveraging event topology analysis to cleanly isolate flow-like behavior and jet modification effects in small collision systems....
The contribution of gluon-photon fusion to dijet production in deeply inelastic scattering is typically analyzed in the small-x regime, whereas quark-photon scattering dominates at large x. The transition between these regimes has received less attention. In this work, we calculate the leading-order, twist-four gluon-photon fusion contribution within a generalized high-twist framework for the...
We systematically investigate the collisional energy loss ($-dE/dz$) and momentum diffusion coefficients ($\kappa_{T/L}$) of heavy quarks traversing the quark-gluon plasma (QGP) across diverse temperature scales. By employing the soft-hard factorization model, we first compute the transport properties at leading order in the QCD coupling, demonstrating that the full results eliminate the...
In a quark-gluon plasma, the enormous total angular momentum generated by non-central collisions evolves over time through spin-orbit coupling interactions, eventually converting into the spin component and thereby inducing spin polarization of the particles.
Our work studies the contribution of the shear flow generated by non-equilibrium medium to the spin alignment of the vector meson J/ψ...
Heavy flavor production serves as an ideal probe of the hadronization mechanism in the hot and dense QCD medium created in relativistic heavy-ion collisions. Heavy quarks acquire elliptic flow through strong coupling with the medium, making v2 a sensitive observable for probing the hadronization time. In this work, we study the production and elliptic flow of Ds and D0 mesons in Pb+Pb...
Angular correlations between heavy quarks provide an important way to study the quark–gluon plasma (QGP) created in high-energy heavy-ion collisions. Current LHC measurements have reported azimuthal correlations of muons from semileptonic heavy-quark decays in 5.02 TeV Pb+Pb and pp collisions, with $p_{T}^{\mu} > 4 GeV $ and $|\eta^{\mu}| < 2.4$.All $\Delta \phi $ distributions show a...
集体流是研究相对论重离子碰撞早期动力学过程的重要可观测量，其中一阶集体流v1对高重子密度核物质状态方程具有较高敏感性。低温高密核物质测量谱仪（CEE）依托HIRFL-CSR平台建设，是我国首台运行于GeV能区的大型核物理实验装置，能够提供能量范围为0.4-1.1...
We have used the parton and hadron cascade model PACIAE together with the Dynamically Constrained Phase-space Coalescence model (DCPC) to study the $T_{cs0}^{*}(2870)^{0}$ production in $pp$ collision at $\sqrt{s}$ = 7 TeV, following the LHCb observation of $T_{cs0}^{*}(2870)^{0}$ in the $B^{-}\to D^{-}D^{0}K^{0}_{S}$ decays in $pp$ collisions at $\sqrt{s}$ = 7, 8, and 13 TeV [PRL...
The search for quark–gluon plasma (QGP)-like collectivity in small collision systems remains a central goal of high-energy nuclear physics. Recent results from O+O collisions suggest that strongly coupled, near-perfect-fluid behavior may emerge even in such small systems, motivating a detailed investigation of jet quenching in systems of reduced size. In this work, we study hadron and jet...
High transverse momentum ($p_T$) jets provide a sensitive probe to the resolving power of the Quark-Gluon plasma (QGP) produced in heavy-ion collisions. In particular, understanding how the medium responds to multi-prong configurations inside jets is essential for a quantitative description of jet quenching and its manifestation in jet substructure sensitive observables.
In this work, we...
We propose that the anisotropic particle distributions in heavy ion collisions can induce a non-vanishing spin alignment of vector meson. We investigate this effect in the production processes of $\phi$ and $K^{*0}$ mesons. For both $\phi$ and $K^{*0}$ produced via S wave scattering, a negative $\delta\rho_{00}$ of order $10^{-3}$ is observed, whose absolute value increases in a more...
