Flavor Phenomenology with Third Generation Quarks and Leptons

该奖项资助了密西西比大学Alakabha Datta的研究活动。众所周知，自然界中有六种夸克和六种轻子构成基本粒子。夸克由三种电荷+2/3（向上、迷人、顶部）和三种电荷-1/3（向下、奇怪、底部）的“味道”组成。这些粒子都在弱相互作用中混合在一起——例如，与上夸克弱相互作用的粒子是下夸克、奇夸克和底夸克的组合。混合的角度和质量都被精确地测量了，但是质量和混合的值是完全神秘的。这就是所谓的“味道难题”。一些夸克和轻子的精确研究，底夸克和顶夸克，以及轻子，对标准模型之外的新物理非常非常敏感。因此，对这些物体的相互作用进行非常精确的研究可以帮助我们理解新的物理学。这反过来又可以在大型强子对撞机（LHC）上产生预期的特征。提议的项目将是探索在风味领域寻找超越标准模型的物理的干净方法，并找到新物理的结构。随着大型强子对撞机历史性地发现了一种新粒子——希格斯玻色子，人们预计在不久的将来，大型强子对撞机将发现许多新粒子。有关这些颗粒的耦合和其他特性的信息可以从风味部门的测量中获得。还有一种可能是，许多新粒子可能超出了大型强子对撞机的范围，在这种情况下，这些粒子的信息可以间接地从风味物理中获得。教育活动将包括培养研究生。将努力通过讲座向公众和科学界代表性不足的群体宣传量子力学和粒子物理学研究的相关性和重要性。将努力让本科生和高中生参与到与PI研究相关的小型项目中来。该项目的目的是在各种不同的领域寻找新的物理学，包括b夸克领域，顶夸克领域以及tau中微子和tau轻子领域。该项目提出的研究活动将集中在b夸克的衰变上，它为大型强子对撞机可能或可能无法触及的新物理学提供了极好的探测。特别是b衰变可能为在大型强子对撞机上新发现的希格斯玻色子之间可能发生的风味变化相互作用提供线索。该项目将研究b衰变中的新物理性质，特别强调b - VV衰变，其中V是矢量介子，在由夸克能级跃迁b - s l^+l^-介导的衰变中，l是带电轻子，以及在半光子衰变b - c({u})tau nu_tau衰变中。该项目将通过CP违反观测值来探测新物理对顶级生产和衰变的影响。最后，该项目计划在第三代轻子领域寻找新的物理现象。该提案将探索从中微子振荡和中微子散射数据中发现和约束非标准中微子相互作用（NSI）的方法，特别是涉及nu_tau和tau轻子。在这项研究中，一个重要的输入将是在获得NSI相互作用的边界时适当地考虑强子效应。这是一个理论项目，在项目中将使用理论粒子物理学家使用的各种工具，如数学计算、数值分析、数值模拟、数据拟合等。

The award funds the research activities of Alakabha Datta at the University of Mississippi. It is known that there are six quarks and six leptons forming the fundamental particles in Nature. The quarks are composed of three "flavors" with charge +2/3 (up, charm, top) and three with charge -1/3 (down, strange, bottom). These particles all mix together in the weak interaction - for example, the particle that interacts weakly with the up quark is a combination of down, strange and bottom quarks. The mixing angles and masses have all been measured precisely, but the values of the masses and mixing are completely mysterious. This is called the "flavor puzzle". Precision studies of some quarks and leptons, the bottom and top quark, and the tau lepton, are very, very sensitive to new physics beyond the standard model. So very precise studies of the interactions of these objects can lead to understanding new physics. That in turn can lead to expected signatures at the Large Hadron Collider (LHC). The proposed project will be to explore clean ways to look for physics beyond the Standard Model in the flavor sector and to find the structure of the new physics. With the historic discovery of a new particle, the Higgs boson, by the LHC it is expected that many new particles will be found at the LHC in the near future. Information on the couplings and other properties of these particles can be obtained from measurements in the flavor sector. It is also likely that many new particles may be beyond the reach of the LHC in which case information on these particles can be indirectly obtained from flavor physics. The educational activities will involve training of graduate students. An effort will be made to inform the general public and underrepresented groups in science about the relevance and importance of quantum mechanics and particle physics research via talks. There will be efforts to involve undergraduate and high school students in mini projects connected to the PI's research.The aim of the project will be to look for new physics in various flavor sectors that include the b quark sector, the top quark sector and the tau neutrino and tau lepton sectors. The proposed research activities of the project will focus on the decays of the b quark that offer excellent probes of new physics that may or may not be within reach of the LHC. In particular b decays may offer clues to possible flavor changing interactions of the newly discovered Higgs boson at the LHC. The project will study the properties of new physics in b decays with special emphasis on B -- VV decays where V is a vector meson, in decays mediated by the quark level transition b -- s l^+l^- where l is a charged lepton and in the semileptonic decays b -- c({u})tau nu_tau decays.The project will probe the effects of new physics in top production and decays via CP violating observables. Finally, this project plans to look for new physics in the third generation lepton sector. The proposal will explore methods for finding and constraining non standard neutrino interactions (NSI) from neutrino oscillation and neutrino scattering data, specially involving the nu_tau and tau leptons. An important input in this investigation will be to properly take into account hadronic effects in obtaining bounds on NSI interactions. This is a theory project and various tools employed by theoretical particle physicists will be used in the project, such as mathematical calculations, numerical analysis, numerical simulation, and data fitting.