Using Jets as a Probe of the Quark Gluon Plasma

使用喷流作为夸克胶子等离子体的探针

• 批准号: 1913696
• 负责人: Rosi Reed
• 金额: $ 21万
• 依托单位: Lehigh University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-15 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1913696&HistoricalAwards=false
• 关键词: Using; Jets; Probe; Quark; Gluon

The building blocks of matter, protons and neutrons, are made up of smaller constituents, which are called quarks and gluons. In collisions of heavy nuclei accelerated to nearly the speed of light, a new state of matter is formed, called the quark-gluon plasma (QGP). In this matter, the protons and neutrons seem to "melt", allowing the quarks and gluons to form a soup-like phase with a viscosity that is nearly as low as possible, earning it the title of a perfect liquid. This project will answer fundamental questions about the QGP, such as how normal matter came into being and how it evolved from the primordial soup of matter which existed just after the Big Bang. The goal of the project is to probe the inner workings of the QGP and determine its properties at much shorter length scales by using high momentum collisions of quarks from within the heavy nuclei collisions. This research will be performed with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), which is located at Brookhaven National Laboratory. This award will also support the PI's mentoring of graduate students and undergraduate students as well as broadening the participation of people from underrepresented groups in STEM through outreach activities. Particle jets are formed in the very initial stages of the heavy nuclei collision, when two quarks or gluons have a high momentum collision. In this collision they are kicked in opposite directions from one another, roughly perpendicular to the beam of heavy ion particles. The quarks and gluons from such an interaction will travel through the QGP, interacting with and losing energy to it. They then fragment and hadronize into a spray of particles which can be measured by the detectors at STAR. The energy scale of the particle jet is inversely proportional to the length scale that it can probe. This effort will focus on observables related to prompt photon-jet correlations at the top collision energies at RHIC. Observables in this category have the advantage that the transverse momentum of jets produced these collisions is explicitly known, due to both conservation of momentum, and the non-interaction of the photon with the QGP. These measurements will be necessary to understand the temperature and energy dependence of key features of theoretical models of the quark-gluon interactions, and thus understand how the strong nuclear force operates.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.

构成物质的基本单元，质子和中子，是由更小的成分组成的，它们被称为夸克和胶子。 在加速到接近光速的重核碰撞中，形成了一种新的物质状态，称为夸克-胶子等离子体（QGP）。 在这种物质中，质子和中子似乎“熔化”，使夸克和胶子形成一种粘度几乎尽可能低的汤状相，使其获得完美液体的称号。 这个项目将回答关于QGP的基本问题，例如正常物质是如何形成的，以及它是如何从大爆炸后存在的原始物质汤中进化而来的。 该项目的目标是探测QGP的内部工作，并通过使用重核碰撞中的夸克的高动量碰撞来确定其在更短长度尺度上的性质。这项研究将在布鲁克海文国家实验室的相对论重离子对撞机（RHIC）上用星星探测器进行。 该奖项还将支持PI对研究生和本科生的指导，并通过外展活动扩大STEM中代表性不足群体的参与。 粒子喷流形成于重核碰撞的初始阶段，即两个夸克或胶子发生高动量碰撞时。 在这种碰撞中，它们被踢向彼此相反的方向，大致垂直于重离子束。这种相互作用产生的夸克和胶子将穿过QGP，与QGP相互作用并失去能量，然后它们碎裂并强子化成粒子喷雾，可以被星星的探测器测量。 粒子喷流的能量尺度与它能探测的长度尺度成反比。 这项工作的重点将是在RHIC的顶部碰撞能量的光子-喷流相关性。 这类观测的优点是，由于动量守恒和光子与QGP的非相互作用，这些碰撞产生的喷流的横向动量是明确已知的。这些测量对于理解夸克-胶子相互作用的理论模型的关键特征的温度和能量依赖性是必要的，从而理解强核力是如何运作的。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。