Electroweak reactions on nuclei from first principles

点击翻译按钮获取中文摘要

Atomic nuclei are dense objects found in the centre of every atom. They are composed of two kinds of nucleons, proton and neutrons, which interact with each other. Nuclei drive the synthesis of the chemical elements, they serve as star fuel and can be used as laboratories to test fundamental symmetries and the Standard Model. The goal of nuclear theory is to provide answers to fundamental questions such as: What is the nature of nuclear forces? How do protons and neutrons tie together to form stable and unstable nuclei? How can we use nuclei to discover properties of fundamental interactions and particles? This proposal aims at tackling these questions by combining two major advances in the theory of nuclei: (i) the modern approach of effective field theory and (ii) novel ab-initio many-body methods, in order to calculate electroweak reactions on nuclei.  Drawing from my previous experience on electromagnetic reactions on light nuclei, I plan to apply innovative theoretical tools, such as the Lorentz integral transform and coupled-cluster theory, to extend ab-initio calculations to nuclei in the medium-mass regime, encompassing both electromagnetic and weak reactions.  I plan to address magnetic and Gamow-Teller responses in neutron-rich nuclei, exploring synergies with the ISAC experimental program. Moreover, with the help of nuclear theory, I plan to contribute to atomic and particle physics addressing important questions that involve the physics of nuclei.  Using few-body exact methods, I propose to calculate nuclear structure corrections in muonic atoms, which are called for by the atomic physics community performing experiments to unravel the mysteries of the so called "proton radius puzzle". Nuclear structure effects are the dominant uncertainties in muonic atoms experiments and can be calculated from nuclear theories with sufficient accuracy. This is key to understand if new forces are at play in muonic atoms. Finally, a long term goal of this proposal is to use the ab-initio coupled-cluster theory to address neutrino-nucleus interactions, with a focus on 16O. The latter are crucial to particle physics experiments aimed at measuring fundamental properties of neutrinos, such as T2K, where presently the data analysis is systematically limited by nuclear physics uncertainties. This Discovery Grant application aims at exploiting synergies with the rare isotope and the particle physics programs at TRIUMF as well as with other experimental programs abroad, and is well aligned with the Canadian Subatomic Physics Long Range Plan. The success of this proposal has potentially a strong scientific impact in nuclear physics,  with important implications also in the atomic and particle physics community. It will considerably strengthen the Canadian efforts in nuclear theory and contribute to the education of the next generation of Canadian nuclear physicists.