Search for Second Generation Leptoquarks using Advanced Data Analysis Methods

这项提议是为了支持北伊利诺伊大学的一位PI，他提议在费米国家加速器实验室的Tevatron的D-Zero实验中搜索第二代轻夸克。PI将与研究生和本科生密切合作，探索进一步开发和应用复杂的数据分析方法。轻夸克是携带轻子和夸克量子数的分数带电粒子，自然地出现在几个动机良好的理论模型中，这些模型超出了粒子物理的标准模型。PI是D-Zero合作的活跃成员，并利用先进的多变量方法在建立世界上对第一代标量轻夸克存在的最佳限制方面发挥了重要作用。随后在Tevatron对第二代和第三代细夸克的搜索没有发现任何信号。然而，继续搜索是很重要的。如果对轻夸克的搜索被证明是成功的，它们的发现将产生直接而深远的影响。如果它们被发现，轻夸克将是自夸克发现以来第一个被发现的根本新的物质状态。对轻夸克性质的详细测量将对理论模型施加严格的限制。正在费米实验室进行的Run II承诺，与Run I期间获得的数据量相比，Run II的数据量将大幅增加。这提供了一个巨大的机会，可以协同努力寻找轻夸克，假设它们存在于Tevatron可以接触到的质量范围内，使用最佳利用数据的分析技术。无论是否发现轻夸克，该项目都具有更广泛的意义，因为它将为参与其中的学生提供有价值的实验物理教育和培训。将要使用的数据分析方法是相当新的、非常通用和强大的。PI的年轻同事不仅将接受当前物理学的全面基础知识，还将接受先进方法的实践培训，这些方法在不同领域找到了重要的应用。

This proposal is a request to support a PI from Northern Illinois University who proposes to search for second-generation leptoquarks at the D-Zero experiment at the Fermi National Accelerator Laboratory's Tevatron. The PI will work closely with graduate and undergraduate students, and explore the further development and application of sophisticated approaches to data analysis. Leptoquarks are fractionally charged particles that carry both lepton and quark quantum numbers and arise naturally in several well motivated theoretical models that go beyond the Standard Model of particle physics. The PI is an active member of the D-Zero collaboration and played a major role, using advanced multivariate methods, in establishing the world's best limits on the existence of first generation scalar leptoquarks. Subsequent searches for second and third generation leptoquarks at the Tevatron have revealed no signals. However, it is important to continue the search. Should the search for leptoquarks prove successful the impact of their discovery would be immediate and profound. Were they to be discovered, leptoquarks would be the first fundamentally new states of matter to be uncovered since the discovery of quarks. Detailed measurements of leptoquark properties would impose severe constraints on theoretical models. Run II, which is in progress at Fermilab, promises a substantial increase in the quantity of data relative to that obtained during Run I. This presents a tremendous opportunity to mount a concerted effort to find leptoquarks, assuming that they exist with masses within reach of the Tevatron, using analysis techniques that make optimal use of data. Whether or not the leptoquarks are found, the project has a broader significance in that it would provide a valuable education in experimental physics and training for the students involved. The data analysis methods to be used are fairly new, extraordinarily versatile and powerful. The PI's younger colleagues would receive not only a thorough grounding in current physics but also practical training in advanced methods that find important applications in a diverse range of fields.