Ab initio nuclear structure calculations of light nuclei

TL;DR

This paper advances ab initio nuclear structure calculations for light nuclei, demonstrating rapid convergence with a new truncation method, and reproduces phenomena like clustering, rotational bands, and beta decay suppression using chiral forces.

Contribution

It introduces a more efficient truncation method for no-core configuration interaction calculations and applies it to reproduce complex nuclear phenomena.

Findings

Faster convergence with total quanta truncation

Reproduction of clustering and rotational structures in 9Be

Accurate modeling of 14C beta decay suppression

Abstract

We perform no-core configuration interaction calculations for nuclei in the p-shell. We show that for typical light nuclei, a truncation on the total number of quanta in the many-body system converges much more rapidly than a full configuration interaction (FCI) truncation, which is a truncation on the single-particle basis space. We present new results for the ground state energies of the Be isotopes with the nonlocal two-body potential JISP16, and discuss emerging phenomena such as clustering and rotational band structures in 9Be. We also show that the anomalously suppressed beta decay of 14C to the ground state of 14N can be reproduced using two- and three-nucleon forces from chiral effective field theory. In particular the structure of the ground state of 14N is sensitive to the three-nucleon force.