Atomic effects in ultra low energy few-nucleon reactions

• Grant number: 22/10580-3
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Duration: May 18, 2023 - May 17, 2024
• Field of knowledge: Physical Sciences and Mathematics - Physics - Nuclear Physics
• Principal Investigator: Tobias Frederico
• Grantee: Tobias Frederico
• Visiting researcher: Jaume Carbonell
• Visiting researcher institution: Institut de Physique Nucléaire Orsay (IPN Orsay), France
• Host Institution: Divisão de Ciências Fundamentais (IEF). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil
• Associated research grant: 17/05660-0 - Theoretical studies of the structure and reactions of exotic nuclei and many-body systems, AP.TEM

Abstract

We aim to study the influence of the electronic effects in nuclear reactions at very low energy.Indeed most of nuclear reaction are performed with atomic targets. If at typical nuclear energies (MeV) the effect of the electronic shells is negligible, it is not the case when the projectile energy is of the same order than the electron binding energies in the target (tens of eV).Our plans is to first consider the neutron-proton case versus the neutron-Hydrogen atom, considered a a 3-body system n-p-e. The incoming neutron interacts with the proton by means of the strong plus the dipole-dipole magnetic interaction. The latter is also present also between the neutron and the electron.We will determine the way in which the very flat "zero"-energy total cross section, determined by the well known singlet and triplet scattering lengths, is modified when the electron dynamics is incorporated at energies going down to the eV and below. Another interesting aspect, dynamically coupled to the previous one, will be the study the low energy fusion process n(H,e)d accessible only due to the presence of the electron in the target.During the visit to ITA the numerical tools for solving this non trivial scattering problem will bedeveloped, in the framework of Faddeev-Merkuriev equations in configuration space. This will pave the way to solve more complex systems. (AU)