New many-body method using cluster expansion diagrams with tensor-optimized antisymmetrized molecular dynamics

TL;DR

This paper introduces a novel many-body computational method that employs cluster expansion diagrams with tensor-optimized antisymmetrized molecular dynamics, improving the accuracy of nuclear structure calculations.

Contribution

The paper presents a new many-body approach using cluster expansion diagrams with independent diagram optimization within TOAMD, enhancing nuclear energy predictions.

Findings

Triple products of correlation functions significantly improve results.

The method accurately reproduces total energies of s-shell nuclei.

Independent diagram optimization enhances solution quality.

Abstract

We propose a new many-body method based on the correlation functions, in which the multiple products of the correlation functions are expanded into the many-body diagrams using the cluster expansion method and every diagram is independently optimized in the total-energy variation. We apply this idea to the tensor-optimized antisymmetrized molecular dynamics (TOAMD) using the bare nucleon-nucleon interaction and show the results of the $s$-shell nuclei within the triple products of the correlation functions of tensor and central-types. We evaluate the effect of the independent optimization of the many-body diagrams on the solutions. It is found that the triple products provides the sizable effect in the present scheme, which results in the good reproduction of the total energy and the Hamiltonian components of nuclei with respect to the few-body calculations.