Studies of Elementary Particles

基本粒子的研究

• 批准号: 0071001
• 负责人: Morris Swartz
• 金额: $ 201.08万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-06-01 至 2003-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0071001&HistoricalAwards=false
• 关键词: Studies; Elementary; Particles

This proposal requests support for a research programin experimental elementary particle physics at the highest laboratory energies. The two hadron collider experiments are CDF at the Fermilab Tevatron and CMS at the Large Hadron Collider (LHC) currently being built at the CERN laboratory in Geneva Switzerland. The CDF collaboration is now finishing a major upgrade of the detector for high-luminosity data taking (Run II) with the Main Injector, currently scheduled to begin on 1 March 2001. The Tevatron energy will increase from 1.8 GeV to 2.0 GeV, and the luminosity is expected to increase by an order of magnitude. Johns Hopkins University physicists are analyzing the present data set (from which the discovery of the top quark was made) while also playing crucial roles in upgrading the silicon vertex detector (SVX II) section of the CDF particle tracking system. This vertex detector is important for all charged particle tracking but is essential to find and measure secondary vertices close to the primary vertex that are characteristic of b-quark decays. Physics research in CDF by this group is concentrated on heavy quark physics and searches for new particles, especially mixing and CP-violation in b-quark decays and Higgs and supersymmetry searches. The CMS experiment will be one of two comprehensive experiments at the LHC. It will open a new energy frontier in the search for physics beyond the Standard Model, in particular the Higgs boson and supersymmetric partners of the known particles. Many of the new processes involve states with b-quarks. This group is working to develop the b-quark vertex detector capabilities of CMS. The vertex detector will use small silicon pixels to provide exceptional position resolution near the pp interaction region. This group has over a decade of experience on silicon detectors from many experiments (Mark II, SDC, CDF, and L3). The group intends its physics analysis efforts to be concentrated on using b-quark decays to study bottom and top physics and to search for phenomena on electroweak symmetry breaking, Higgs bosons, and supersymmetry.The L3 experiment is now taking LEP II data above theW+W- threshold, allowing precise measurement of W boson properties, most notably in mass and couplings, and allowing searches for new particles, especially the Higgs boson in both the Standard Model and supersymmetry. The group intends to continue to participate in L3 data taking through the end of LEP running (expected to be fall 2000) and intends to complete L3 analysis work in mid to late 2001. This group will concentrate on the search for the Higgs boson, exploring both Standard Model and supersymmetric signatures.

该提案要求支持在最高实验室能量下的实验基本粒子物理学研究计划。 这两个强子对撞机实验分别是费米实验室Tevatron的CDF和目前正在瑞士日内瓦欧洲核子研究中心实验室建造的大型强子对撞机（LHC）的CMS。CDF合作目前正在完成探测器的重大升级，以便利用主注入器进行高亮度数据采集（运行II），目前计划于2001年3月1日开始。 Tevatron能量将从1.8 GeV增加到2.0 GeV，亮度预计将增加一个数量级。 约翰霍普金斯大学的物理学家们正在分析目前的数据集（从中发现了顶夸克），同时也在升级CDF粒子跟踪系统的硅顶点探测器（SVX II）部分中发挥了至关重要的作用。 这个顶点探测器对所有带电粒子的追踪都很重要，但对于发现和测量靠近主顶点的次顶点是必不可少的，这是b夸克衰变的特征。 该小组在CDF的物理研究集中在重夸克物理和寻找新粒子，特别是在b夸克衰变和希格斯和超对称搜索中的混合和CP破坏。CMS实验将是LHC的两个综合实验之一。 它将开辟一个新的能源领域，寻找超越标准模型的物理学，特别是希格斯玻色子和已知粒子的超对称伙伴。 许多新的过程都涉及b夸克态。 这个小组正在努力开发CMS的b夸克顶点探测器能力。 顶点探测器将使用小的硅像素来提供pp相互作用区域附近的特殊位置分辨率。 该小组在硅探测器方面有十多年的经验，来自许多实验（Mark II，SDC，CDF和L3）。 该小组打算将其物理分析工作集中在使用b夸克衰变来研究底部和顶部物理，并寻找电弱对称性破缺，希格斯玻色子和超对称现象。L3实验现在正在采取LEP II数据高于W +W-阈值，允许精确测量W玻色子属性，最显着的是质量和耦合，并允许搜索新粒子，特别是标准模型和超对称中的希格斯玻色子。 该小组打算继续参与L3数据采集，直至LEP运行结束（预计2000年秋季），并打算在2001年中至年底完成L3分析工作。该小组将集中精力寻找希格斯玻色子，探索标准模型和超对称签名。