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.

该奖项资助教授乔恩Pumplin，丹尼尔Stump和C.-对这一项目的支持将有助于理解高能物理实验所揭示的物理宇宙的基本性质-组成宇宙的粒子及其相互作用。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由量子色动力学（QCD）理论描述。拟议中的研究涉及QCD理论和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QCD的理解和确定质子中部分子的概率分布是必要的。 通过理解这些分布，就有可能采取质子与质子的相互作用（这是在LHC发生的），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学是必不可少的，并且对于提取例如希格斯玻色子信号是必要的。 这些概率分布被称为“CTEQ部分子分布函数”，其中CTEQ意味着“QCD的协调理论-实验项目”。 该项目在MSU和CTEQ暑期学校培训研究生和博士后研究员理论高能物理。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MSU和密歇根州赞助的暑期项目体验物理的机会。如上所述，由此产生的CTEQ帕顿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：Fermilab（Batavia，IL）、RHIC（Brookhaven，NY）、DESY（Hamburg，德国）和CERN（日内瓦，瑞士）。 虽然费米实验室和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HERA运行II的最终数据仍然需要在获得后纳入本分析。拟议的研究将延续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。作为对QCD研究的补充，该小组还将研究SM的电弱（EW）部分，该部分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上对W、Z、顶夸克对、单顶夸克和希格斯玻色子产生的测量，包括包含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，部分子分布的细化是必要的，在EW部门的进展，无论是在更高的精度测试SM和探测高能对撞机中的新物理效应。