Recent Developments in Few-Nucleon Scattering

TL;DR

This paper reviews recent progress in modeling few-nucleon scattering, highlighting the importance of three-nucleon forces and comparing different models' effectiveness in describing light nuclei and scattering phenomena.

Contribution

It provides a comparative analysis of various three-nucleon force models and applies the Kohn Variational Principle to N-d scattering, addressing existing challenges.

Findings

Simultaneous reproduction of three- and four-nucleon binding energies remains difficult.

Different three-nucleon force models show varying success in describing light nuclei.

Application of the Kohn Variational Principle offers a promising approach for N-d scattering analysis.

Abstract

Using modern nucleon-nucleon interactions in the description of the $A=3,4$ nuclei, it is not possible to reproduce both the three- and four-nucleon binding energies simultaneously. This is one manifestation of the necessity of including a three-nucleon force in the nuclear Hamiltonian. Several models of the three-nucleon force exist and are applied in the description of light nuclei. However, as it is discussed here, a simultaneous description of the three- and four-body binding energies and the $n-d$ doublet scattering length seems to be problematic. Accordingly, a comparative study of some of these models is performed. In a different analysis, we study applications of the Kohn Variational Principle, formulated in terms of integral relations, to describe $N-d$ scattering processes.