Elucidating Jet Quenching and Medium Response Mechanisms via Hard Probes in Relativistic Heavy-ion Collisions

通过硬探针阐明相对论重离子碰撞中的喷射淬火和介质响应机制

• 批准号: 1019387
• 负责人: Jiangyong Jia
• 金额: $ 46.5万
• 依托单位: SUNY at Stony Brook
• 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 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1019387&HistoricalAwards=false
• 关键词: Elucidating; Jet; Quenching; Medium; Response

At extremely high temperature and density, the normal nuclear matter we experience every day "melts'" into the so called Quark-gluon plasma (QGP) phase consisting of "quasi-free'" quarks and gluons, a phase believed to have existed during the first 10 microseconds after our universe was born in the Big Bang. This QGP can be created by heating matter above a temperature of 170 millon electron volts. Experimentally, this is done by colliding two large nuclei (typically Gold or Lead) at very high energy. The resulting hot and dense fireball is expected to expand under its own pressure, and cool down. Properties of the QGP such as its temperature, pressure, chemical potential, viscosity, diffusion coefficient, speed of sound, etc. can be deduced from thousands of particles emitted from the fireball and detected with large scale particle detectors surrounding the interaction region. Such studies are being carried out in the PHENIX experiment at the Relativistic Heavy-ion Collider (RHIC) and planned for the ATLAS experiment at the Large Hadron Collider (LHC), respectively. This project is focused on a set of exclusive measurements that can establish the properties of the high-density matter created at RHIC via the PHENIX detector, as well as applying some of these measurement techniques at LHC using the ATLAS detector. Specifically, we will probe the properties of this matter via measurements of high-energy single jets and back-to-back jet pairs (di-jets). The research will improve our present understanding of the fundamental nature of the matter under extreme conditions, and therefore has a broad impact on other fields of endeavor such as astrophysics and super-string theories. Participation by graduate students and undergraduate students is expected throughout the program. The PHENIX experiment provide a diverse array of research topics at all levels of education, as well as an excellent working environment involving interactions between hundreds of scientists in the field, and unique opportunities for career development in programming, hardware, leadership and academics.

在极高的温度和密度下，我们每天经历的正常核物质“熔化”成所谓的夸克胶子等离子体（QGP）相，由“准自由”夸克和胶子组成，这一相据信在我们的宇宙在大爆炸中诞生后的前 10 微秒。 这种 QGP 可以通过将物质加热到 1.7 亿电子伏以上的温度来产生。 在实验上，这是通过以非常高的能量碰撞两个大原子核（通常是金或铅）来完成的。 由此产生的又热又密的火球预计会在自身压力下膨胀并冷却。 QGP 的特性，如温度、压力、化学势、粘度、扩散系数、声速等，可以从火球发射的数千个粒子中推断出来，并用相互作用区域周围的大型粒子探测器进行检测。 此类研究分别在相对论重离子对撞机（RHIC）的 PHENIX 实验中进行，并计划在大型强子对撞机（LHC）的 ATLAS 实验中进行。 该项目的重点是一系列独特的测量，这些测量可以通过 PHENIX 探测器确定 RHIC 产生的高密度物质的特性，并使用 ATLAS 探测器在 LHC 上应用其中一些测量技术。 具体来说，我们将通过测量高能单射流和背靠背射流对（双射流）来探测这种物质的性质。 这项研究将提高我们目前对极端条件下物质基本性质的理解，因此对天体物理学和超弦理论等其他领域产生广泛影响。 整个项目预计会有研究生和本科生的参与。 PHENIX 实验提供了各个教育层次的多样化研究主题，以及涉及该领域数百名科学家之间互动的优良工作环境，以及编程、硬件、领导力和学术方面职业发展的独特机会。