Relativistic Heavy Ion Collision Studies at the LHC and RHIC

LHC 和 RHIC 的相对论重离子碰撞研究

• 批准号: 0970048
• 负责人: Thomas Humanic
• 金额: $ 150万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0970048&HistoricalAwards=false
• 关键词: Relativistic; Heavy; Ion; Collision; Studies

This is a three-year project primarily to carry out experiments with relativistic heavy ion collisions. The goals for this program are three-fold. The first goal is to study the space-time properties of the extremely dense matter created in collisions between heavy nuclei at the highest achievable energies. It is believed that Quark Matter is created in these collisions, characterized by a large collection of quarks and gluons, the microscopic components of normal matter such as protons and neutrons. The second goal is to study the bulk phase structure of Quantum Chromodynamics (QCD), believed to be the correct theory to describe interactions between quarks and gluons. This will be achieved by varying the conditions of the collision to lower energies in order to probe the transition(s) between normal matter and Quark Matter. The third goal is to take the tools developed to study bulk physics in heavy ion collisions and apply them to proton-proton collisions at similar energies. We will look particularly for collective behavior, such as hydrodynamic flow, in these collisions. If our initial reports of such flow in proton-proton collisions are confirmed at these higher energies, this raises important issues about the nature of flow, and the nature of the initial state of these collisions. In the present project, relativistic heavy ion collisions will be studied with gold-gold collisions at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL), and with lead-lead collisions at the Large Hadron Collider (LHC) at CERN in Geneva. RHIC, which started delivering beams in Summer 2000, is the highest energy heavy ion accelerator now in operation. In order to look for signatures that a phase transition to Quark Matter has taken place, one must study the properties of the particles produced in the collisions, such as particle momenta and multiplicities of each type that can be detected (e.g. pions, kaons, protons, and more exotic particles). This will be done at RHIC using the large acceptance detectors of the STAR experiment, which can sample most of the interesting particles per collision. The information obtained in this way can be used to determine, for example, the physical size of the interaction region (using two-particle interferometry), the temperatures reached in the collisions (from particle momentum distributions) and exotic particle production such as strange baryons. In addition, studies of proton-proton and lead-lead collisions at even higher energies at the LHC with the ALICE experiment will begin by April 2010. The LHC will provide beams 30 times higher in center-of-mass energy than RHIC, i.e. cosmic ray energies, making for a useful comparison with results from RHIC. There are broader impacts to society of this project in the areas of education, technology and computing. Since undergraduate students, graduate students and postdoctoral researchers will play key roles in this project, training will be provided to these groups in how to carry out research in large collaborations and in general problem solving skills. This research requires large-scale computing in order to acquire and analyze data on the teraflop and terabyte scale, and new methods in information science, such as computing grid systems, will be developed which can enhance the computing power of society as a whole.

这是一个为期三年的项目，主要是进行相对论重离子碰撞的实验。 该计划的目标是三倍。 第一个目标是研究在最高可实现的能量的重核之间碰撞中产生的极度密集物质的时空特性。 据信，夸克物质是在这些碰撞中创建的，其特征是大量夸克和胶子，这是正常物质的显微镜成分，例如质子和中子。 第二个目标是研究量子染色体动力学（QCD）的大量相结构，被认为是描述夸克与胶子之间相互作用的正确理论。 这将通过将碰撞条件变为较低的能量来实现，以探测正常物质和夸克物质之间的过渡。 第三个目标是采用开发的工具来研究重离子碰撞中的散装物理，并将其应用于类似能量的质子 - 普罗顿碰撞。 在这些碰撞中，我们将特别研究集体行为，例如流体动力流。 如果我们在这些较高的能量中确认了质子质子碰撞中这种流动的初步报道，这将提出有关流量性质以及这些碰撞最初状态的重要问题。 在本项目中，将在Brookhaven国家实验室（BNL）的相对论重离子对撞机（RHIC）上研究相对论的重离子碰撞，并在Geneva的CERN大型强子对撞机（LHC）进行铅铅碰撞。 RHIC从2000年夏季开始运送横梁，是目前正在运行的最高能量重离子加速器。 为了寻找已经发生了夸克物质的相位过渡的签名，必须研究碰撞中产生的颗粒的特性，例如粒子矩和可检测到的每种类型的多重性（例如乳头，kaons，质子，质子和更多外来的颗粒）。 这将在RHIC上使用Star实验的大型接受探测器进行，该检测器可以每碰撞采样大多数有趣的颗粒。 以这种方式获得的信息可用于确定相互作用区域的物理大小（使用两粒子干涉法），在碰撞中达到的温度（来自粒子动量分布）和奇异的粒子产生，例如奇怪的baryons。 此外，使用Alice实验开始对LHC的更高能量的质子 - 质子和铅铅碰撞的研究将于2010年4月开始。LHC将在质量中心能量中提供比RHIC的束高30倍，即宇宙射线能量，从而使RHIC的结果与Rhic的结果相比。 在教育，技术和计算领域，对该项目的社会产生了更大的影响。 由于本科生，研究生和博士后研究人员将在该项目中扮演关键角色，因此将向这些小组提供如何在大型合作和一般解决问题的技能方面进行研究。 这项研究需要进行大规模计算，以获取和分析TERAFLOP和TERABYTE量表的数据，并且将开发信息科学中的新方法，例如计算网格系统，以增强社会的计算能力。