Electroweak interactions in hadronic systems

强子系统中的电弱相互作用

• 批准号: SAPIN-2015-00045
• 负责人: Blunden, Peter
• 金额: $ 2.77万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762935
• 关键词: Electroweak; interactions; hadronic; systems

The objective underlying my research program is understanding the fundamental properties of nucleons and nuclei through electromagnetic and electroweak interactions.In the electromagnetic sector, calculations of two--photon exchange (TPE) radiative corrections have been instrumental in resolving the discrepancy between measurements of electron--nucleon scattering form factors using Rosenbluth and polarization-transfer techniques. Pioneering calculations by our group have focussed on a hadronic approach to evaluating the model--dependent TPE amplitudes, including the contribution of nucleon resonances. Experimental interest in TPE has grown considerably in the last decade, in part because it has implications for a number of precision measurements, such as the proton radius puzzle and parity--violating electron scattering. It is also important for extracting proton and neutron form factors, electro-production of resonances and pions, and nuclear form factors. Experiments seeking to directly identify TPE effects are underway in several laboratories, and we are involved in providing theoretical support and predictions.Precision low--energy experiments in atomic parity--violation and in parity--violating electron--proton scattering are a vital complement to direct tests of the Standard Model. They also give information about the structure of the proton, such as its weak charge and strangeness content. These low--energy measurements have the potential to give constraints on new physics, provided that the critical radiative corrections are understood. In particular, there are uncertainties associated with hadronic physics that are always present, even in purely leptonic processes.A major component of my research is aimed at unravelling these hadronic contributions and their associated uncertainties. Complementary to the TPE program, electroweak radiative corrections from two--boson exchange involve physics on both low--energy hadronic (resonance region) and high--energy (deep -inelastic and Regge region) scales. A significant advance in recent years is to reduce the model-dependence of these contributions by using dispersion relations based on data. Our work shows how constraints from parton distribution functions, together with new data on parity-violating electron scattering in the resonance region, can significantly reduce the uncertainties on the corrections compared to previous estimates. In addition to atomic parity--violation and the weak charge of the proton (the Qweak experiment), this work is significant for a new generation of upcoming precision experiments at Jefferson Lab and Mainz utilizing parity--violating electron scattering (e.g. Moller and SOLID).My research gives students excellent training in analytical and computational aspects of theoretical physics, as well as opportunities to work with international researchers.

我的研究计划的基本目标是通过电磁和电动相互作用来理解核子和核的基本特性。在电磁扇区中，对两个 - 光子交换（TPE）辐射校正的计算在解决了使用电子分散量和极性范围的范围之间的差异来解决差异和范围之间的差异。我们小组的开创性计算集中在评估依赖模型的TPE振幅的HADRONIC方法上，包括核子共振的贡献。在过去的十年中，对TPE的实验兴趣已经大大增长，部分原因是它对许多精确测量（例如质子半径拼图和平等）具有影响。这对于提取质子和中子形式，共振和乳腺的电产生以及核形态也很重要。在几个实验室中，寻求直接识别TPE效应的实验正在进行中，我们参与提供理论支持和预测。原子奇偶校验和偶然性 - 侵略和均衡 - 侵害电子 - proton-proton散射的较低 - 能量实验是一个重要的补充，以直接测试标准模型的测试。他们还提供有关质子结构的信息，例如其弱电荷和陌生内容。这些低的能量测量可能会对新物理学产生限制，前提是了解临界辐射校正。特别是，即使在纯粹的麻the过程中，也存在与Hadronic物理学有关的不确定性。与TPE计划相辅相成，来自两玻色子交换的Electroweak辐射校正涉及低 - 能量的耐药（共振区域）和高能（深度弹性和雷格区）尺度的物理。近年来，一个重大进展是通过基于数据的分散关系来降低这些贡献的模型依赖性。我们的工作表明，与以前的估计值相比，与谐振区域中平均侵入电子散射的新数据以及有关均衡电子散射的新数据如何显着降低了校正的不确定性。除了原子奇偶元 - 质子的侵害和质子的弱电荷（QWEAK实验）外，这项工作对于杰斐逊实验室的新一代即将到来的精确实验非常重要，它利用了平等的电子散射（例如moller and Solid）（例如，molter and Solid）。我的研究为学生提供了分析和计算方面的良好的研究，并在国际上进行了研究，以及实用的范围，以及对摩尔学的机会进行研究。