Ab Initio Calculations of the Carbon and Oxygen Isotopes: Energies, Correlations, and Superfluid Pairing

TL;DR

This paper uses ab initio nuclear lattice calculations with chiral interactions to analyze energies, correlations, and superfluid pairing in neutron-rich carbon and oxygen isotopes, revealing universal correlation patterns.

Contribution

It introduces detailed ab initio calculations of neutron-rich isotopes, highlighting correlation behaviors and pairing mechanisms with potential universality.

Findings

Good agreement with observed binding energies

Correlation dependence on isospin $T_z$ among neutrons

Distinct interaction patterns for paired and unpaired neutrons

Abstract

We perform \textit{ab initio} nuclear lattice calculations of the neutron-rich carbon and oxygen isotopes using high-fidelity chiral interactions. We find good agreement with the observed binding energies and compute correlations associated with each two-nucleon interaction channel. For the isospin $T=1$ channels, we show that the dependence on $T_z$ provides a measure of the correlations among the extra neutrons in the neutron-rich nuclei. For the spin-singlet S-wave channel, we observe that any paired neutron interacts with the nuclear core as well as its neutron pair partner, while any unpaired neutron interacts primarily with only the nuclear core. For the other partial waves, the correlations among the extra neutrons grow more slowly and smoothly with the number of neutrons. These general patterns are observed in both the carbon and oxygen isotopes and may be universal features that appear in many neutron-rich nuclei.