Halo Structures in p-Shell Hypernuclei with Natural Orbitals

TL;DR

This paper demonstrates that natural orbitals improve convergence and provide structural insights in ab initio hypernuclear calculations, revealing hyperon halo structures in p-shell hypernuclei.

Contribution

It extends natural orbital methods to hypernuclei, showing enhanced convergence and the ability to identify hyperon halo structures in p-shell hypernuclei.

Findings

Natural orbitals accelerate convergence in hypernuclear calculations.

Identification of hyperon halo structures in {}He5, A=6, and A=7 hypernuclei.

Radial wavefunctions reveal species-specific structural information.

Abstract

We extend the concept of natural orbitals as an optimized single-particle basis for ab initio nuclear many-body calculations to hypernuclei and show that their superior properties, in particular accelerated convergence and independence of the underlying harmonic-oscillator frequency, can be directly transferred to the hypernuclear regime as demonstrated in no-core shell model calculations for selected p-shell hypernuclei. Moreover, the radial single-particle wavefunctions associated with the natural-orbital basis yield important structural information with respect to the different particle species allowing us to identify a hyperon halo in {\Lambda}He5. We further explore nucleonic and hyperonic halo structures in A=6 and A=7 singly-strange hypernuclei based on one-body densities and point-particle radii obtained from no-core shell model calculations with realistic interactions from chiral effective field theory.