Global QCD Analysis and Precision Electroweak Physics in High Energy Collider Phenomenology

高能对撞机现象学中的全局 QCD 分析和精密电弱物理

• 批准号: 1417326
• 负责人: Chien-Peng Yuan
• 金额: $ 72万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1417326&HistoricalAwards=false
• 关键词: Global; QCD; Analysis; Precision; Electroweak

This award funds the research activities of Professors Jon Pumplin, Daniel Stump and C.-P. Yuan at the Michigan State University (MSU).Support for this project will contribute to understanding the fundamental nature of the physical universe--the particles that comprise it and their interactions--as revealed by experiments in high energy physics. Current understanding of high energy physics is embodied in the Standard Model (SM). Protons and neutrons, and all other strongly interacting particles, are composed of fundamental particles called partons (quarks and gluons). Interactions between the partons are described by the theory of Quantum Chromodynamics (QCD). The proposed research involves the interplay between QCD theory and experimental data from many experiments, including recent experiments at the CERN Large Hadron Collider (LHC). This global analysis of data is necessary to deepen the understanding of QCD, and to determine the probability distributions of the partons in the proton. By understanding these distributions, it is possible to take interactions of protons with protons (which is what happens at the LHC) and determine the underlying quark-quark, quark-gluon and gluon-gluon interactions. This is essential for determining the underlying physics of the process, and was necessary for extracting, for example, the Higgs boson signal. These probability distributions are called "CTEQ Parton Distribution Functions", where CTEQ means "Coordinated Theoretical-Experiment Project of QCD". The project trains graduate students and postdoctoral fellows in theoretical high energy physics at MSU and at CTEQ summer schools. It also provides opportunities for undergraduate students to participate in forefront research through the REU program, and for high school teachers and middle school students to experience physics through summer programs sponsored by MSU and the State of Michigan.As noted, the resulting CTEQ Parton Distribution Functions have been essential to the interpretation of experiments at the world's leading high energy collider facilities: Fermilab (Batavia, IL), RHIC (Brookhaven, NY), DESY (Hamburg, Germany), and CERN (Geneva, Switzerland). Although the colliders at Fermilab and DESY have been turned off, data from those facilities are still important; in particular, final data from HERA run II are still to be incorporated in the present analysis when they become available. The proposed research will continue the PIs' world-leading contributions to lepton-hadron and hadron-hadron collider phenomenology. Complementary to the research on QCD, the group will also study the Electroweak (EW) sector of the SM, which is extremely successful in explaining and predicting experimental data spanning a range in energy from the atomic scale to the Z boson and top quark masses. Measurements of W, Z, top quark pair, single top quark and Higgs boson productions at the LHC, including both inclusive rates and relevant kinematical distributions, will provide major new input to the understanding of parton distributions during the next few years. At the same time, refinements of the parton distributions are necessary for progress in the EW sector, both for testing the SM in greater precision and for probing New Physics effects in high energy colliders.

该奖项资助了Jon Pumplin、Daniel Stump和c . p . p .等教授的研究活动。袁教授在密歇根州立大学（MSU）说。对这个项目的支持将有助于理解物理宇宙的基本性质——组成宇宙的粒子及其相互作用——正如高能物理学实验所揭示的那样。目前对高能物理的理解体现在标准模型（SM）中。质子和中子，以及所有其他强相互作用的粒子，都是由称为部分子（夸克和胶子）的基本粒子组成的。部分子之间的相互作用用量子色动力学（QCD）理论描述。提出的研究涉及QCD理论与许多实验数据之间的相互作用，包括最近在欧洲核子研究中心大型强子对撞机（LHC）的实验。这种数据的全局分析对于加深对量子cd的理解和确定质子中各部分的概率分布是必要的。通过了解这些分布，就有可能得到质子与质子之间的相互作用（这就是在大型强子对撞机中发生的情况），并确定潜在的夸克-夸克、夸克-胶子和胶子-胶子相互作用。这对于确定该过程的基本物理原理至关重要，对于提取希格斯玻色子信号也是必要的。这些概率分布称为“CTEQ Parton分布函数”，其中CTEQ意为“QCD协调理论实验项目”。该项目在密歇根州立大学和CTEQ暑期学校培养理论高能物理学的研究生和博士后。它还为本科生提供了通过REU项目参与前沿研究的机会，并为高中教师和中学生提供了通过密歇根州立大学和密歇根州赞助的暑期项目体验物理学的机会。如上所述，由此产生的CTEQ Parton分布函数对于解释世界领先的高能对撞机设施的实验至关重要：费米实验室（巴达维亚，IL）， RHIC（布鲁克海文，NY）， DESY（汉堡，德国）和CERN（日内瓦，瑞士）。尽管费米实验室和DESY的对撞机已经关闭，但来自这些设施的数据仍然很重要；特别是，海地环境评估第二轮的最后数据在获得后仍将纳入本分析。拟议的研究将继续pi在轻子-强子和强子-强子对撞机现象学方面的世界领先贡献。作为QCD研究的补充，该小组还将研究SM的电弱（EW）部分，这在解释和预测从原子尺度到Z玻色子和顶夸克质量的能量范围内的实验数据方面非常成功。在LHC上测量W， Z，顶夸克对，单顶夸克和希格斯玻色子的产生，包括包括率和相关的运动学分布，将在未来几年内为理解部分子分布提供重要的新输入。与此同时，对部分子分布的改进对于电子战领域的进展是必要的，无论是为了更精确地测试SM，还是为了探测高能对撞机中的新物理效应。