Regular Article - Theoretical Physics
Wigner SU(4) symmetry, clustering, and the spectrum of C
Institut für Kernphysik, Institute for Advanced Simulation and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425, Jülich, Germany
2 Facility for Rare Isotope Beams and Department of Physics and Astronomy, Michigan State University, 48824, East Lansing, MI, USA
3 Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, 53115, Bonn, Germany
4 Tbilisi State University, 0186, Tbilisi, Georgia
Accepted: 6 September 2021
Published online: 20 September 2021
We present lattice calculations of the low-lying spectrum of C using a simple nucleon–nucleon interaction that is independent of spin and isospin and therefore invariant under Wigner’s SU(4) symmetry. We find strong signals for all excited states up to MeV above the ground state, and explore the structure of each state using a large variety of cluster and harmonic oscillator trial states, projected onto given irreducible representations of the cubic group. We are able to verify earlier findings for the clustering in the Hoyle state and the second state of C. The success of these calculations to describe the full low-lying energy spectrum using spin-independent interactions suggest that either the spin-orbit interactions are somewhat weak in the C system, or the effects of clustering are diminishing their influence. This is in agreement with previous findings from ab initio shell model calculations.
© The Author(s) 2021
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