第十一届粒子所“青年之星”2025年度学术论坛

The photon radiation induced by rescattering in a magnetized medium is investigated in relativistic heavy-ion collisions. Within the high-energy limit, the photon emission rate and the associated electromagnetic energy loss are derived using the Gyulassy-Levai-Vitev formalism at first order in opacity, for a quark jet propagating a quark-gluon plasma under a background magnetic field....

Directed and elliptic flow ($v_1$ and $v_2$), are sensitive to the dynamics during the early stages of the system
evolution and equation of state of the medium.
The $v_1$ slope ($dv_1/dy$) at mid-rapidity of net-baryons is expected to be sensitive to the first-order phase transition, while the Number of Constituent Quark (NCQ) scaling of elliptic flow is regarded as a signal of formation of...

Motivated by the first LHCb searches for the rare $\bar{B}_{s,d}^{0} \to J/\psi\mu^{+}\mu^{-}$ decays, we perform a detailed study of these processes within the QCD factorization formalism. Since the transverse size of the $J/\psi$ meson is small in the heavy quark mass limit, this formalism is generally expected to hold for these decays. We include both the leading- and the...

This Letter presents the world’s most precise measurements of direct CP asymmetries in $B^{+} \to K^0_{\mathrm{S}} \pi^{+}$ and $B^{+} \to K^0_{\mathrm{S}} K^{+}$ decays. The measurement precision in the theoretically clean $B^{+} \to K^0_{\mathrm{S}} \pi^{+}$ mode reaches the $\cal{O}$(0.01) level for the first time, providing a stringent test of the Standard Model prediction of zero CP...

麻醉剂在外科手术和治疗干预中至关重要，但它们具有副作用和不同程度的有效性，因此需要提供更精确和可控效果的新型麻醉剂。针对中枢神经系统中的主要抑制性受体——γ氨基丁酸（GABA）受体，可以增强其抑制作用，从而可能减少副作用，同时提高麻醉药的效力。在这项研究中，我们考虑了蛋白质-蛋白质相互作用 (PPI) 网络中的 4000 多种蛋白质和超过 150 万种已知的结合化合物，介绍了基于 24 种 GABA 受体亚型的 GABA 受体介导的麻醉的蛋白质组学学习。我们开发了相应的药物-靶标相互作用网络，以确定新型麻醉剂设计的潜在先导化合物。为了确保稳健的蛋白质组学学习预测，我们整理了一个数据集，其中包含 PPI 网络内 980 个目标池中的 136...

We present a Bayesian holographic model constructed by integrating the equation of state and baryon number susceptibility at zero chemical potential from lattice QCD. The model incorporates error estimates derived from lattice data. With this model, we systematically investigate the thermodynamic properties of the 2+1-flavor QCD system. Using Bayesian Inference, we perform precise calibration...

Dibaryons, exotic states composed of six quarks, have long been a subject of interest in understanding the strong interaction beyond conventional hadrons. Among these, strange dibaryons, which contain strange quarks, offer an important role of studying the hyperon-nucleon ($YN$) and hyperon-hyperon ($YY$) interactions . Of particular interest are the spin-0 $H$ ($S$ = -2) and the spin-2...

Recent CMS results reveal that jets with extremely high multiplicity exhibit novel substructure patterns not seen in ordinary jets, including long-range correlations. However, standard Monte Carlo tools struggle to access this regime due to its rarity and complexity. In this work, we develop a theoretical framework to study high-multiplicity jets, incorporating both multiplicity evolution and...

Charmless two-body B-meson decays to baryon-antibaryon pairs serve as key probes for strong interaction dynamics and CP violation but remain underexplored. This is the first observation of the rare baryonic decay B->p Lambda_bar. The significantly improved branching fraction measurement and the first measurement of the weak decay parameter in this work are of great interests for testing...

报告人：Qiang Wang (王强)，博研 (导师：周代梅)
关联论文预印本号：arXiv: 2506.20145

摘要：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...

This study investigates the impact of nucleon-nucleon correlations on heavy-ion collisions using the hadronic transport model SMASH in $\sqrt{s_{\rm NN}}=3$ GeV $^{197}\rm Au$+$^{197}\rm Au$ collisions. We developed an innovative Monte Carlo sampling method that incorporates both single-nucleon distributions and nucleon-nucleon correlations. By comparing three initial nuclear configurations –...

We employ the Veneziano quantum chromodynamics (VQCD) model, a holographic approach that dynamically simulates essential QCD characteristics, including linear mass spectra, confinement, asymptotic freedom, and magnetic charge screening, while incorporating quark flavor effects. Using this model, we first calculate the proton mass spectrum and the wave function, incorporating anomalous...

We develop a neural network model, based on the processes of high-energy heavy-ion collisions, to study and predict several experimental observables in Au+Au collisions. We present a data-driven deep learning framework for predicting multiple bulk observables in Au+Au collisions at RHIC energies. A single neural network is trained exclusively on experimental measurements of charged-particle...

X.-N. Zhu, Defu Hou, X.-L. Sheng, Phys. Rev. D 112, 056011 (2025)

We develop a theoretical framework for the production of K+K- pairs through the decay of ϕ mesons produced from a thermal background, based on the Nambu-Jona-Lasinio (NJL) model. The differential production rate of K+K- is related to the self-energy of the ϕ meson, incorporating the contributions of the quark loop at...

本文研究了一类分段光滑不连续一维映象的动力学。当周期轨道失稳时，系统会进入混沌状态。而不连续性的出现导致了边界碰撞分岔的发生，可以使稳定的周期轨道转变为混沌状态或者另外一个稳定的周期状态。在这类转变点的附近，常常伴随着吸引子共存现象。 此外，随控制参数减小出现周期递增现象。得到了求解这类不连续映象在任意参数下边界碰撞分岔临界控制参数的一般方法。基于稳定性和边界碰撞分岔的解析分析, 获得了双参数平面中系统动力学的相平面, 讨论了系统的动力学行为，发现了三类余维-2分岔点， 并给出了其坐标通式。同时，在相平面中还发现了余维分岔点的融合，构成一类特殊的三相点，并解析得到其存在的条件。

doi: 10.7498/aps.75.20251167

Within the Color Glass Condensate (CGC) effective field theory, we investigate the long-range rapidity correlations in proton-lead (p-Pb) collisions at √ s NN = 5.02 TeV. As expected, the long-range rapidity correlations rebound after bottoming, which is successfully reproduced by the CGC. It is also found that the correlation rebound appears around the sum of the saturation momenta of the...

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 $v_{2}$...

Nuclear modifications to collinear parton distribution functions are conventionally quantified by the ratios $ r^{\textrm{A}}_i(x,Q^2) = f^\textrm{A,proton}_i(x,Q^2) / f^\textrm{proton}_i(x,Q^2) $. For a given nucleus $A$, these ratios generally depend on the parton momentum fraction $ x $, the probing scale $ Q^{2} $, and the parton species $ i $. Determining these dependencies relies on a...

We propose a novel centrality definition-independent method for analyzing higher-order cumulants, specifically addressing the challenge of volume fluctuations that dominate in low-energy heavy-ion collisions. This method reconstructs particle number distributions using the Edgeworth expansion, with parameters optimized via a combination of differential evolution algorithm and Bayesian...

A nonextensive (3+1)-dimensional hydrodynamic model for multiparticle production processes, NEX-CLVisc, is developed in the framework of CLVisc where the viscous corrections are turned off. It assumes that the nonextensive effects consistently exist in the initial conditions set by the optical Glauber model, the equation of state and the hadron kinetic freeze-out procedure. The model is then...

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 $v_2$ a sensitive observable for probing the hadronization time. In this Letter, we study the production and elliptic flow of $D_s$ and $D^0$ mesons in...

在这项研究中，我们提出一种新颖的方法，通过分析 $\pi^{-}$ 与 $\pi^{+}$ 产额差 $\Delta n_{\pi}$ 的逐事件分布，来预测金核的中子皮厚度。借助 SMASH 模型，我们模拟了$\sqrt{s_{\mathrm{NN}}}=3$~GeV 下的超偏心 Au+Au 碰撞。结果显示，$\Delta n_{\pi}$ 的平均值、$(\pi^{-}+\pi^{+})$ 与 $(\pi^{-}-\pi^{+})$ 之间的皮尔逊相关系数，均与中子皮厚度有显著的线性关系；更重要的是，逐事件分布中连接不同 $\Delta n_{\pi}$ 值点的直线斜率也表现出同样的线性依赖，其中，最敏感的$\Delta n_{\pi}$ 对为 $(-1,1)$、$(-1,2)$、$(0,1)$ 和 $(0,2)$，为实验测定提供了全新的可观测量。最后，在完全相同的初始条件下对比...

Neural network methods are increasingly applied to solve phase transition problems, particularly in identifying critical points in non-equilibrium phase transitions, offering more convenience compared to traditional methods. In this paper, we analyze the (1+1)-dimensional and (2+1)-dimensional directed percolation models using an autoencoder network. We demonstrate that single-step...

We study the relaxation dynamics of the three-dimensional kinetic Ising model along the phase boundary, focusing on the relaxation behavior [1] and the evolution of the underlying free-energy landscape[2]. We find that the average equilibration time increases significantly as the temperature moves far below the critical point T_c, and exhibits ultraslow relaxation along the first-order phase...

Chaos is omnipresent in nature, and its understanding provides enormous
social and economic benefits. However, the unpredictability of chaotic
systems is a textbook concept due to their sensitivity to initial conditions,
aperiodic behaviour, fractal dimensions, nonlinearity and strange attractors.
In this work, we introduce, for the first time, chaotic learning, a novel
multiscale...

Link prediction in complex networks--identifying the missing or future connections--remains a cornerstone problem for understanding network evolution and function, yet existing methods struggle to balance computational efficiency with theoretical rigor across heterogeneous topologies. This work introduces a physically principled framework, Diffusion Distance with Personalized PageRank (D-PPR),...

Hydrodynamic models fail to describe the near-equal $v_3 / v_2$ ratio observed in ultra-central heavy-ion collisions, despite their success in other centrality classes. This failure can not be resolved by adjusting the shear viscous coefficient, as shear viscosity suppresses higher-order anisotropic flows more strongly, leading to an underestimation of $v_3$ when $v_2$ matches experimental...

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...

The wetting transition in the one-dimensional cluster Ising model with opposite boundary fields is studied. Tuning one boundary field while fixing another leads to the occurrence of phase transitions, where the transition points depend on the cluster coupling. Furthermore, the phase diagram is divided into three regions with different phase transition. For weak and strong cluster coupling, the...

探究 J/ψ和 Υ(1S)这类重矢量介子对于理解重离子碰撞中形成的夸克胶子等离子体（QGP）至关重要。本研究通过在全息QCD中引入旋转介质，考察了旋转效应对 J/ψ和 Υ(1S)性质的影响。研究发现，温度、化学势以及旋转半径效应会促进 J/ψ和 Υ(1S)态在介质中的解离过程。这种旋转诱导的效应对于横向的重矢量介子比纵向更为显著。本文首次在全息框架下研究了均匀旋转系统半径对矢量介子谱的影响，发现旋转半径的增大会促进 J/ψ和 Υ(1S)的解离。我们还发现，在较大旋转半径下，垂直于旋转角速度方向的解离比平行方向的解离更为显著。

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 $v_2$.

However, calculating...

We present a lattice QCD study of the chiral properties of (2+1)-flavor QCD in background magnetic fields at zero temperature with physical pion masses. Simulations are performed using the highly improved staggered quark (HISQ) action across four different lattice spacings to enable a controlled continuum extrapolation. We compute the renormalized chiral condensates, pseudoscalar meson masses,...

In high-energy heavy-ion collisions, energetic partons traverse the quark-gluon plasma (QGP) and deposit energy into the medium, leading to Mach-cone-like jet-induced medium response which modifies the internal structure of jet and impacts jet substructures, such as jet shape and jet fragmentation function. However, accurately simulating jet-induced medium responses requires a complete model...

在标准模型有效场理论（SMEFT）框架中，若仅依据味量子数并要求重子数与轻子数守恒，可构造出 2499 个独立的维六算符，其对应的威尔逊系数皆为独立自由参数。如此高的参数自由度不仅削弱了理论的预测性，也限制了不同物理过程之间的关联性。

在引入 U(2)^5 味对称性后，上述情况发生显著改变：该对称性能够大幅减少独立威尔逊系数的数量，使得多个看似无关的过程可由同一组有效参数统一描述。同时，U(2)^5 对称性还能有效抑制 SMEFT 中可能出现的过大味改变中性流（FCNC），并在对称性结构允许的范围内，自然解释为何第三代 Yukawa 耦合能够远大于前两代，从而在味物理中提供了更为合理的一致性描述。

In this work, a simulation and analysyis framework for the N$\nu$DEx experiment is presented.
N$\nu$DEx aims to search for the neutrinoless double beta decay in $^{82}$Se using a high pressure $^{82}$SeF$_6$ gas time projection chamber (TPC). Direct charge collection for the drifting ion charge carriers using low-noise CMOS charge sensors is the main feature of the experiment.

Using...