第十一届粒子所“青年之星”2025年度学术论坛

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...