Nuclear states projected from a pair condensate

TL;DR

This paper introduces a computational method using pair condensates with good particle number and angular momentum projection to model various nuclear shapes and spectra, offering a tractable approach for medium- to heavy-mass nuclei.

Contribution

It develops a novel approach combining pair condensates with angular momentum projection, capable of modeling complex nuclear deformations and spectra.

Findings

Successfully reproduces spherical, vibrational, and rotational spectra.

Comparable accuracy to projected Hartree-Fock and full configuration-interaction methods.

Applicable to medium- and heavy-mass nuclei.

Abstract

Atomic nuclei exhibit deformation, pairing correlations, and rotational symmetries. To meet these competing demands in a computationally tractable formalism, we revisit the use of general pair condensates with good particle number as a trial wave function for even-even nuclei. After minimizing the energy of the condensate, we project out states with good angular momentum with a fast projection technique, allowing for general triaxial deformations. To show applicability, we present example calculations from pair condensates in several model spaces, and compare against projected Hartree-Fock and full configuration-interaction shell model calculations. This approach successfully generates spherical, vibrational and rotational spectra, demonstrating potential for modeling medium- to heavy-mass nuclei.