Benchmarking a Multi-Phase Transport for Relativistic Heavy Ion Collisions

相对论性重离子碰撞多相传输的基准测试

• 批准号: 2012947
• 负责人: Zi-Wei Lin
• 金额: $ 29.57万
• 依托单位: East Carolina University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2012947&HistoricalAwards=false
• 关键词: Benchmarking; Multi; Phase; Transport; Relativistic

The soup of elementary particles, quarks and gluons, that characterized the universe for a few millionths of a second after the Big Bang, known as the quark-gluon plasma (QGP), has been created in high energy heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) in the USA and the Large Hadron Collider (LHC) in Europe. Such experiments allow physicists to study the QGP properties and understand the strong interaction at extreme temperatures and densities. A rich set of data has been measured from these experiments, including the recent evidence that the QGP is even formed in small collision systems. Hydrodynamics-based models as well as transport models have been quite successful in describing many observables. However, because transport models include non-equilibrium dynamics, they are expected to be different from hydrodynamic models for small systems. Open questions include the onset and origin of the observed collective motion of the produced particles from small to large systems, and how an interacting system transitions from the dilute limit to the hydrodynamic limit. This project focuses on using the improved transport method to address these questions, with the PI mentoring students in this research at both graduate and undergraduate levels. The improved multi-phase transport model as a public code also serves as a convenient event generator and testbed for the nuclear physics community.The main goal of this project is to address open questions regarding the QGP properties by improving the theoretical foundation and accuracy of a multi-phase transport model. This model contains a parton cascade phase and a bulk hadronization model in addition to fluctuating initial conditions and a later hadron cascade phase. The objectives include the following: i) benchmark and improve the accuracy of the parton transport method in describing the evolution of the dense matter; ii) improve the hadronization process, including starting the quark coalescence around a critical energy density instead of the parton kinetic freeze-out and applying fragmentation to heavy-flavor partons at high transverse momentum; iii) improve a multi-phase transport model with the verified parton cascade and improved hadronization and then make direct comparisons with experimental observables such as anisotropic flows. With the improved transport model constrained by bulk observables, properties of the dense matter such as the shear viscosity can also be quantitatively studied and compared with results from other approaches such as viscous-hydrodynamic models.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在大爆炸之后的宇宙中，宇宙的特征是宇宙的汤，被称为Quark-Gluon等离子体（QGP），在美国和大型Hadron Collider（RHIC）的相对性重离子碰撞机（RHIC）中创建了高能量重离子碰撞（QGP）。这样的实验使物理学家可以研究QGP特性，并了解极端温度和密度的强烈相互作用。从这些实验中测量了一系列数据，包括最近的证据表明QGP甚至在小型碰撞系统中形成。基于流体动力学的模型以及运输模型在描述许多可观察到的东西方面非常成功。但是，由于传输模型包括非平衡动力学，因此预计它们与小型系统的流体动力学模型有所不同。空旷的问题包括观察到的从小型系统到大型系统产生的颗粒的集体运动的开始和起源，以及相互作用的系统如何从稀释极限到流体动力学极限的转变。该项目的重点是使用改进的运输方法来解​​决这些问题，PI指导学生在研究生和本科级别的这项研究中。改进的多相运输模型作为公共法规也是一个方便的事件生成器，并为核物理社区进行了测试。该项目的主要目标是通过提高多相运输模型的理论基础和准确性来解决有关QGP属性的开放问题。该模型还包含Parton级联相和批量的强调模型，此外除了波动的初始条件和后来的强子级联相。目标包括以下内容：i）基准并提高了Parton运输方法描述密集物质演变的准确性； ii）改善强调过程，包括围绕临界能量密度而不是Parton动力学冻结，并在高横向动量下将碎片施加到重味部分； iii）改善具有经过验证的Parton级联反应并改善强环化的多相传输模型，然后与实验性观察物（如各向异性流量）进行直接比较。借助大量可观察到的改进的运输模型，诸如剪切粘度之类的密集物质的特性也可以进行定量研究，并将其与其他方法的结果进行比较，例如粘性 - 流动力模型。该奖项反映了NSF的法定任务，并认为通过基金会的知识优点和更广泛的crietia crietia crietia cribitia criperia criperia criperia criperia criperia criperia criperia criperia recectia rectuniation均值得通过评估。

项目成果

Calculating QCD Phase Diagram Trajectories of Nuclear Collisions using a Semi-analytical Model

使用半解析模型计算核碰撞的 QCD 相图轨迹

• DOI: 10.1051/epjconf/202327601012
• 发表时间: 2023
• 期刊: EPJ Web of Conferences
• 作者: Mendenhall, Todd;Lin, Zi-Wei
• 通讯作者: Lin, Zi-Wei

Calculating the initial energy density in heavy ion collisions by including the finite nuclear thickness

• DOI: 10.1103/physrevc.103.024907
• 发表时间: 2020-12
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: T. Mendenhall;Zi-Wei Lin

Implication of two-baryon azimuthal correlations in pp collisions at LHC energies on the QGP

• DOI: 10.1016/j.physletb.2022.137063
• 发表时间: 2021-12
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: Liuyao Zhang;Jinhui Chen;Wei Li;Zi-Wei Lin

Thermodynamics of partonic matter in relativistic heavy-ion collisions from a multiphase transport model

• DOI: 10.1103/physrevc.105.034912
• 发表时间: 2021-02
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Han-Sheng Wang;G. Ma;Zi-Wei Lin;Wei-jie Fu

Left-right splitting of elliptic flow due to directed flow in heavy ion collisions

• DOI: 10.1103/physrevc.106.054910
• 发表时间: 2021-09
• 期刊: Physical Review C
• 影响因子: 3.1
• 作者: Chao Zhang;Zi-Wei Lin