Elucidating the Fundamental Properties of the Nucleon with Dispersive Techniques

现代核物理学和粒子物理学关注的是理解自然界的基本参数和对称性。最近，这个谜题的一个关键的新部分随着获得诺贝尔奖的中微子风味振荡的发现而变得可行，这表明中微子的质量与标准模型的范式相反。今天，中微子物理领域进入了精确时代，基于加速器的中微子振荡实验在美国和世界的实验计划中占据了中心位置。要了解探测器中中微子与原子核的相互作用，需要对强相互作用——将原子核结合在一起的力——进行精确的建模。PI将使用最先进的分析技术来完成这项工作，重点关注与费米实验室和其他地方的中微子实验最直接相关的数量。因此，该项目将为支持这些实验突破提供必要的理论基础。它还将为学生和年轻研究人员提供良好的培训场所。这个项目的重点是在模拟GeV能量下的中微子相互作用中起关键作用的一个特定的物理领域：核子轴向形状因子。它描述了核子的结构，核子不是点状粒子，但其结构仍不为人所知。PI和她的合作者将基于手性微扰理论和色散技术的方法，开发一个基于物理的框架来精确地模拟这种形状因子。此外，通过各种分析约束的应用，例如电流守恒，将建立一个对晶格进行数值评估的桥梁。还将探讨与各种电子散射数据的一致性。这将支持托马斯杰斐逊实验室最先进的核物理实验，特别是GlueX或CLAS，以及即将在费米实验室和世界范围内进行的精确中微子核散射实验。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Modern nuclear physics and particle physics are concerned with understanding the fundamental parameters and symmetries of nature. A crucial new piece of this puzzle has recently become available with the Nobel-prize-winning discovery of the neutrino flavor oscillations, which showed that neutrinos had masses contrary to the paradigm of the Standard Model. Today, the field of neutrino physics enters the precision era, with accelerator-based neutrino oscillation experiments taking center stage in the experimental program in the US and in the world. To understand neutrino interactions with nuclei in the detector requires accurate modeling of strong interactions—the force that binds the nucleus together. The PI will do this using state-of-the-art analytical techniques, focusing on the quantities of most direct relevance to neutrino experiments at Fermilab and elsewhere. This project will thus provide the necessary theoretical foundations needed to support these experimental breakthroughs. It will also provide excellent training ground for students and young researchers. The focus of this project is be on a specific piece of physics that plays a crucial role in modeling neutrino interactions at GeV energies: the nucleon axial form factor. It describes the structure of the nucleon which is not a point-like particle but has a structure that is still not well known. The PI and her collaborators will develop a physics-based framework to accurately model this form factor, based on the methods of chiral perturbation theory and dispersive techniques. Moreover, a bridge to numerical evaluations on the lattice will be established by applications of various analytical constraints, such as current conservation. Agreement with various electron scattering data will also be explored. This will support state-of-the-art nuclear physics experiments at Thomas Jefferson Laboratory, particularly GlueX or CLAS, as well as the upcoming precision neutrino-nucleus scattering experiments at Fermilab and worldwide.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.