Structure of $^{23}$Al from a multi-channel algebraic scattering model based on mirror symmetry

TL;DR

This paper models the spectrum of the proton-rich nucleus $^{23}$Al using a multichannel algebraic scattering approach, predicting known and unobserved states based on mirror symmetry with $^{23}$Ne.

Contribution

It is the first to comprehensively model most of the known spectrum of $^{23}$Al and predict additional states using the MCAS method with mirror symmetry considerations.

Findings

Six low-energy states with known $J^$ are matched.

Predicted properties of four unobserved states.

Suggested existence of several additional states.

Abstract

The proton-rich nucleus $^{23}$Al has a ground state just 123 keV below the proton drip-line, and as a result comparatively little is known experimentally about its properties, as with many such nuclei. Theoretical investigations have tended to model exclusively the ground and first one to three excited states known. In this paper, we theoretically model most of the known spectrum, and predict what states may as yet be unobserved. We use the multichannel algebraic scattering (MCAS) method to describe states as resonances of a valence proton coupled to a $^{22}$Mg rotor core. Six states with low-excitation energies and defined $J^\pi$ are matched, and we make the first prediction of the properties of four others and propound the possible existence of several more.