Charge Radius of Neutron-Deficient ^{54}Ni and Symmetry Energy Constraints Using the Difference in Mirror Pair Charge Radii

Skyy V Pineda; Kristian König; Dominic M Rossi; B Alex Brown; Anthony Incorvati; Jeremy Lantis; Kei Minamisono; Wilfried Nörtershäuser; Jorge Piekarewicz; Robert Powel; Felix Sommer

doi:10.1103/PhysRevLett.127.182503

Charge Radius of Neutron-Deficient ^{54}Ni and Symmetry Energy Constraints Using the Difference in Mirror Pair Charge Radii

Phys Rev Lett. 2021 Oct 29;127(18):182503. doi: 10.1103/PhysRevLett.127.182503.

Authors

Skyy V Pineda^{1

2}, Kristian König¹, Dominic M Rossi^{3

4}, B Alex Brown^{1

5}, Anthony Incorvati^{1

5}, Jeremy Lantis^{1

2}, Kei Minamisono^{1

5}, Wilfried Nörtershäuser³, Jorge Piekarewicz⁶, Robert Powel^{1

5}, Felix Sommer³

Affiliations

¹ National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
² Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
³ Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany.
⁴ GSI Helmholtzzentrum für Schwerionenforschung mbH, Planckstr. 1, 64291 Darmstadt, Germany.
⁵ Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA.
⁶ Department of Physics, Florida State University, Tallahassee, Florida 32306, USA.

PMID: 34767412
DOI: 10.1103/PhysRevLett.127.182503

Abstract

The nuclear root-mean-square charge radius of ^{54}Ni was determined with collinear laser spectroscopy to be R(^{54}Ni)=3.737(3) fm. In conjunction with the known radius of the mirror nucleus ^{54}Fe, the difference of the charge radii was extracted as ΔR_{ch}=0.049(4) fm. Based on the correlation between ΔR_{ch} and the slope of the symmetry energy at nuclear saturation density (L), we deduced 21≤L≤88 MeV. The present result is consistent with the L from the binary neutron star merger GW170817, favoring a soft neutron matter EOS, and barely consistent with the PREX-2 result within 1σ error bands. Our result indicates the neutron-skin thickness of ^{48}Ca as 0.15-0.21 fm.