Analysis of clustering phenomena in ab initio approaches

TL;DR

This paper introduces a new ab initio method that explicitly incorporates cluster effects in nuclear systems, improving the calculation of nuclear properties and revealing significant non-clustered contributions.

Contribution

The paper develops a basis combining No-Core Shell Model and cluster wave functions, enabling more accurate ab initio calculations of nuclear clustering phenomena.

Findings

Accurate computation of 8Be binding energy.

Quantification of cluster channel spectroscopic factors.

Discovery of significant non-clustered basis contributions.

Abstract

An approach for explicit consideration of cluster effects in nuclear systems and accurate ab initio calculations of cluster characteristics of nuclei is devised. The essential block of the approach is a construction of a basis which incorporates both conventional No-Core Shell Model wave functions and translationally-invariant wave functions of various cluster channels. The results of computations of the total binding energies of 8Be nucleus as well as the spectroscopic factors of cluster channels (amount of clustering) are presented. An unexpected fresh result of the rigorous study is that the contribution of "non-clustered" components of the basis to the total binding energy is great even in the typical cluster systems such as the discussed nucleus.