Modification of Heavy Quarkonia Production in Nuclear Collisions

核碰撞中重夸克尼亚产量的改进

• 批准号: 2013115
• 负责人: Anthony Frawley
• 金额: $ 30万
• 依托单位: Florida State 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=2013115&HistoricalAwards=false
• 关键词: Modification; Heavy; Quarkonia; Production; Nuclear

We now know that most visible matter is composed of nucleons (protons and neutrons), which in turn are made up of more elementary constituents: quarks and gluons. A new form of matter called the quark-gluon-plasma (QGP) can be created through very energetic collisions of nucleons. This QGP is thought to replicate the conditions in the early Universe a millionth of a second after the Big Bang. This award supports the study of the production of quark-antiquark pairs (mesons, called charmonium and bottomonium) made from heavy quarks in collisions of protons with protons, of protons with gold nuclei, and of gold nuclei with gold nuclei. This will further the understanding of the interactions of heavy quark mesons with the QGP, with the ultimate goal of better understanding the mechanisms that govern the evolution of the strongly interacting QGP, the most strongly coupled liquid ever created. Understanding the QGP is critical to our understanding of the interactions between quarks and gluons. The research will be conducted in large part by graduate students. They will write doctoral dissertations based on the results, under the mentorship of the principal investigator. There will also be significant involvement of undergraduate students in the research, providing them with a good introduction to physics research methods and tools. The research will be conducted using data from collisions at the top Relativistic Heavy Ion Collider (RHIC) collision energy of root(sNN) = 200 GeV, and will focus in two areas. The first area is the study of charmonium production in p+Au collisions using existing data - recorded by the PHENIX experiment at RHIC from p+Au (and 3He+Au) collisions. This research is aimed at better understanding the mechanisms by which charmonium production is modified when it takes place in a nuclear target. That modification is governed by the way that gluons interact inside a nucleus, which is still imperfectly understood. Also, measuring the modification of charmonium production in a target provides a baseline for measurements of charmonium modification by the QGP in Au+Au collisions. The second area is the study of bottomonium production in p+Au and Au+Au collisions using future measurements by the sPHENIX experiment at RHIC. This will further the understanding of bottomonium interactions with the QGP produced in heavy ion collisions. Because charmonium and bottomonium mesons have very different properties, they provide complementary information about interactions within the QGP. The proposed research includes a significant contribution to the development of tracking techniques and software that must be in place before the sPHENIX detector, currently under construction, is commissioned in 2022.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.

我们现在知道，大多数可见物质是由核子（质子和中子）组成的，而核子又由更基本的成分组成：夸克和胶子。 一种称为夸克胶子等离子体（QGP）的新物质形式可以通过核子的高能碰撞产生。 这个QGP被认为复制了宇宙大爆炸后百万分之一秒的早期宇宙的条件。 该奖项支持研究质子与质子、质子与金核以及金核与金核碰撞中重夸克产生的夸克-反夸克对（介子，称为粲偶素和底偶素）。 这将进一步理解重夸克介子与QGP的相互作用，最终目标是更好地理解控制强相互作用QGP（有史以来最强耦合的液体）演化的机制。 理解QGP对我们理解夸克和胶子之间的相互作用至关重要。这项研究将在很大程度上由研究生进行。他们将在主要研究者的指导下，根据研究结果撰写博士论文。本科生也将大量参与研究，为他们提供物理研究方法和工具的良好介绍。这项研究将使用顶部相对论重离子对撞机（RHIC）根（sNN）= 200 GeV碰撞能量的碰撞数据进行，并将集中在两个领域。第一个领域是利用RHIC PHENIX实验从p+Au（和3 He +Au）碰撞中记录的现有数据研究p+Au碰撞中的粲偶素产生。这项研究的目的是更好地了解在核靶中发生的粲偶素生产被修改的机制。这种变化是由胶子在核内相互作用的方式决定的，这一点仍然没有完全理解。此外，测量靶中的粲偶素产生的修饰为在Au+Au碰撞中通过QGP测量粲偶素修饰提供了基线。第二个领域是研究在p+Au和Au+Au碰撞中的bottomonium生产，使用RHIC的sPHENIX实验的未来测量。这将进一步了解bottomonium与重离子碰撞产生的QGP的相互作用。因为粲偶素和底偶素介子有非常不同的性质，它们提供了关于QGP内相互作用的补充信息。拟议的研究包括对跟踪技术和软件开发的重大贡献，这些技术和软件必须在sPHENIX探测器（目前正在建设中）于2022年投入使用之前到位。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。