Flavor Phenomenology with Third Generation Quarks and Leptons

该奖项资助密西西比大学阿拉卡巴·达塔的研究活动。众所周知，自然界中有六个夸克和六个轻子构成基本粒子。夸克由电荷+2/3(向上、魅力、顶部)和电荷-1/3(向下、奇怪、底部)的三种“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、奇怪夸克和底部夸克的组合。混合角和质量都得到了精确测量，但质量和混合的值完全是神秘的。这就是所谓的“味道之谜”。对一些夸克和轻子，底夸克和顶夸克，以及陶轻子的精确研究，对标准模型以外的新物理非常、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。这反过来可以在大型强子对撞机(LHC)上产生预期的签名。拟议的项目将探索在香料部门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的粒子--希格斯玻色子，预计在不久的将来，大型强子对撞机将会发现许多新的粒子。有关这些颗粒的偶联和其他性质的信息可以从香料部门的测量中获得。许多新粒子也有可能超出了大型强子对撞机的探测范围，在这种情况下，有关这些粒子的信息可以从味道物理中间接获得。教育活动将涉及研究生的培训。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研究的相关性和重要性。将努力让本科生和高中生参与与PI的研究相关的迷你项目。该项目的目标是在不同的香料部门寻找新的物理，包括b夸克部门、顶级夸克部门以及tau中微子和tau轻子部门。该项目拟议的研究活动将集中在b夸克的衰变上，这些b夸克提供了对新物理的极好探测，这些新物理可能在大型强子对撞机触手可及的范围内，也可能不在其范围内。特别是，b衰变可能为大型强子对撞机上新发现的希格斯玻色子的味道变化相互作用提供线索。该项目将研究b衰变中新物理的性质，特别是B-VV衰变，其中V是矢量介子，由夸克能级跃迁b-S L^+L^-介导的衰变中，L是带电轻子，在半轻子衰变中b-c({u})tau nu_tau衰变。该项目将探索新物理在顶层产生和衰变中的影响。最后，该项目计划在第三代轻子领域寻找新的物理。该计划将探索从中微子振荡和中微子散射数据中发现和限制非标准中微子相互作用(NSI)的方法，特别是涉及nu_tau和tau轻子的数据。这项研究的一个重要内容将是在获得NSI相互作用的界限时适当考虑强子效应。这是一个理论项目，理论粒子物理学家将在项目中使用各种工具，如数学计算、数值分析、数值模拟和数据拟合。

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.