Two- and three-alpha systems with nonlocal potential

TL;DR

This paper introduces a method to fit local or nonlocal potentials to both two-body and three-body experimental data, addressing the nonlocal nature of interactions due to quantum effects, exemplified by the alpha-alpha system.

Contribution

It presents a novel approach for simultaneously fitting two- and three-body data with nonlocal potentials, specifically applied to alpha particle interactions.

Findings

Successfully reproduces two- and three-alpha experimental data

Demonstrates the importance of nonlocal potentials in modeling composite particle interactions

Provides fitted parameters for a Pauli-correct nonlocal optical model

Abstract

Two body data alone cannot determine the potential uniquely, one needs three-body data as well. A method is presented here which simultaneously fits local or nonlocal potentials to two-body and three-body observables. The interaction of composite particles, due to the Pauli effect and the indistinguishability of the constituent particles, is genuinely nonlocal. As an example, we use a Pauli-correct nonlocal fish-bone type optical model for the $\alpha-\alpha$ potential and derive the fitting parameters such that it reproduces the two-$\alpha$ and three-$\alpha$ experimental data.