Determination of the nuclear incompressibility from the rapidity-dependent elliptic flow in heavy-ion collisions at beam energies 0.4\emph{A} - 1.0\emph{A} GeV
Yongjia Wang, Chenchen Guo, Qingfeng Li, Arnaud Le Fevre, Yvonne Leifels, Wolfgang Trautmann
Heavy-ion-collision measurements in combination with transport model simulations serve as important tools for extracting the nuclear incompressibility. However, uncertainties in transport models (or model dependence) partly affect the reliability of the extracted result. In the present work, by using the recently measured data of rapidity-dependent flows, we constrain the incompressibility of nuclear matter and analyse the impact of model uncertainties on the obtained value. The method is based on the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model in which the Skyrme potential energy-density functional is introduced. Three different Skyrme interactions which give different incompressibilities varying from $K_0$=201 to 271 MeV are adopted. The incompressibility is deduced from the comparison of the UrQMD model simulations and the FOPI data for rapidity-dependent elliptic flow in Au+Au collisions at beam energies 0.4\emph{A} - 1.0\emph{A} GeV. The elliptic flow $v_2$ as a function of rapidity $y_0$ can be well described by a quadratic fit $v_2=v_{20} + v_{22}\cdot y_0^2 $. It is found that the quantity $v_{2n}$ defined by $v_{2n}=|v_{20}|+|v_{22}|$ is quite sensitive to the incompressibility $K_0$ and the in-medium nucleon-nucleon cross section, but not sensitive to the slope parameter $L$ of the nuclear symmetry energy. With the FU3FP4 parametrization of the in-medium nucleon-nucleon cross section, an averaged $K_0 = 220 \pm 40$~MeV is extracted from the $v_{2n}$ of free protons and deuterons. However, remaining systematic uncertainties, partly related to the choice of in-medium nucleon-nucleon cross sections, are of the same magnitude ($\pm 40$~MeV). Overall, the rapidity dependent elliptic flow supports a soft symmetric-matter equation-of-state.
Rapidity-dependent charge dynamics in high-energy nuclear collisions from dynamical core-corona initialization
Zhejiang Institute of Modern Physics, Department of Physics, Zhejiang University（浙江大学现代物理研究所）；Department of Physics, Sophia University（上智大学物理学部）；Department of Space Systems Engineering, Kyushu Institute of Technology（九州工业大学宇宙系统工学科）；Akita International University（秋田国际大学）
Longitudinal Dynamics of Large and Small Systems from a 3D Bayesian Calibration of RHIC Top-energy Collision Data
Vanderbilt University（范德堡大学）；Wayne State University（韦恩州立大学）；RIKEN BNL Research Center, Brookhaven National Laboratory（理化学研究所布鲁克海文研究中心，布鲁克海文国家实验室）；Universidade de São Paulo（圣保罗大学）；Duke University（杜克大学）；McGill University（麦吉尔大学）；University of California, Berkeley（加州大学伯克利分校）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Universidade Federal Fluminense（弗鲁米嫩塞联邦大学）
Probing nuclear compressibility via fragmentation in Au+Au reactions at 35 AMeV
采用分子动力学方法研究了35 MeV/核子的$^{197}$ Au + $^{197}$ Au外围碰撞中的碎裂过程，探讨了低密度区核物质的可压缩性.采用软硬两种状态方程，分析了带电荷$3\leq Z \leq 80$的带电粒子在不同周边几何条件下的不同碎片种类、快度谱和多重数的产额.碎片的生产被发现是相当不敏感的核子-核子截面的选择，使我们能够约束核物质的可压缩性。计算的带电粒子多重性与实验数据的比较表明，核物质的\emph{soft}性质的偏好。
The QCD Pomeron in Ultraperipheral Heavy Ion Collisions: IV. Photonuclear Production of Vector Mesons
在QCD色偶极图中研究了超周边重离子碰撞中矢量介子的光核产生，着重讨论了饱和模型。计算了A + A --> V + A + A（V = ρ，ω，phi，J/Psi）过程的积分截面和快度分布，并给出了RHIC和LHC能量下轻核和重核散射的理论估计。与最近的STAR数据的ρ介子相干产生的比较也被提出。此外，我们还计算了RHIC、Tevatron和LHC能区质子-质子碰撞中矢量介子的光生。
Heavy-ion Physics at a Fixed-Target Experiment Using the LHC Proton and Lead Beams (AFTER@LHC): Feasibility Studies for Quarkonium and Drell-Yan Production
Nonequilibrium Models of Relativistic Heavy-Ion Collisions
我们回顾了从AGS到RHIC能量的各种流体动力学和输运模型对集体流观测的结果。本文对CERN强子集体流实验的现状进行了评述。我们强调的重要性，从1至50 A $\cdot$ GeV的流激发函数：在这里的流体动力学模型预测的崩溃的$v_1$ -流和$v_2$ -流在$\sim 10$ A $\cdot$ GeV，在40 A $\cdot$ GeV，它最近已被观察到的NA 49合作。由于强子再散射模型预测更大的流量比观察到在这个能量，我们解释为一级相变的证据，在高重子密度$ρ_B$的观察。此外，椭圆流$v_2$射流抑制的连接进行了检查。实验证明，小射流破碎不会伪造集体流动。此外，详细的输运研究表明，远侧喷流抑制只能部分（$<$ 50%）是由于强子再散射。此外，$v_1, v_2$的符号变化更接近于束流快度，这与在62.5、130和200 A $\cdot$ GeV的RHIC数据中出现的高密度一级相变有关。
Characterizing nuclear modification effects in high-energy O-O collisions at energies available at the CERN Large Hadron Collider: A transport model perspective
