Quarks in cosmos and in heavy ion collisions

宇宙和重离子碰撞中的夸克

• 批准号: 183818-2009
• 负责人: Zhitnitsky, Ariel
• 金额: $ 5.46万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=513951
• 关键词: Quarks; cosmos; heavy; ion; collisions

There are fundamental links between cosmology and particle physics, which have been well established at all scales. In particular, the physics of the early Universe, baryogenesis, cosmological nucleosynthesis, etc. is based on our modern understanding of particle physics. This realization has made the early Universe a marvelous laboratory for studying fundamental physics, in particular the vacuum structure of the theory. Conversely, knowledge of the behavior of fundamental physics at high temperature gives information about what happened shortly after the Big Bang. What is more remarkable is the fact that these phenomena at the QCD scale can be, in principle, experimentally tested in heavy ion collisions at RHIC (relativistic heavy ion collider), Brookhaven National Labaratory, and in the nearest future at LHC (Geneva, Switzerland) where such unusual environment can be achieved. The goal of the project is: the study of QCD as part of the standard model in an unusual environment when temperature T, chemical potential and the so-called theta- parameter are non-zero. This knowledge gives a reliable information about what have happened 14 billion years ago soon after the Big Bang at the temperature T = 170 MeV. The understanding of the corresponding phase diagram (as a function of these external parameters) is one of the most challenging problems in QCD. This problem with nonzero theta parameter has never been studied previously in the literature, though it is likely that theta parameter was non-zero during the QCD phase transition few moments after the Big Bang. Due to the differences in interactions between quarks and antiquarks in the presence of the theta parameter the local separation of baryon charges may take place. This phenomenon can be tested at RHIC. In fact, the phenomenon of charge separation has been studied in our recent paper with D. Kharzeev. What is more important: this effect has been experimentally tested at RHIC. Preliminary results support our findings. If confirmed, it would be the first ever observation of the P and CP violation in strong interactions. Second part of the project is the application of the ideas mentioned above for needs of astrophysics and cosmology.

宇宙学和粒子物理学之间有着根本的联系，这在所有尺度上都已经得到了很好的建立。特别是，早期宇宙的物理学，重子生成，宇宙核合成等都是基于我们对粒子物理学的现代理解。 这一认识使早期宇宙成为研究基础物理的奇妙实验室，特别是理论的真空结构。相反，高温下基础物理学行为的知识提供了大爆炸后不久发生的事情的信息。 更值得注意的是，QCD尺度下的这些现象原则上可以在布鲁克海文国家实验室的RHIC（相对论重离子对撞机）和最近的将来在LHC（瑞士日内瓦）的重离子碰撞中进行实验测试，在那里可以实现这种不寻常的环境。该项目的目标是：研究QCD作为标准模型的一部分 在一个不寻常的环境中，当温度T，化学势和所谓的θ参数不为零时。 这一知识提供了关于140亿年前在T = 170 MeV的大爆炸后不久发生的事情的可靠信息。理解相应的相图（作为这些外部参数的函数）是QCD中最具挑战性的问题之一。这个问题与非零θ参数从来没有研究过以前的文献中，虽然它是可能的，θ参数是非零的QCD相变的几个时刻后，大爆炸。在θ参数存在的情况下，由于夸克和反夸克之间相互作用的差异，重子电荷的局域分离可能发生。这一现象可以在RHIC上得到检验。事实上，电荷分离现象在我们最近的论文中已经研究过了 与D. Kharzeev。更重要的是：这种效应已经在RHIC实验中得到了检验。 初步结果支持我们的发现。如果得到证实，这将是有史以来第一次在强相互作用中观察到P和CP破坏。 该项目的第二部分是将上述想法应用于天体物理学和宇宙学的需要。