Correlations between charge radii differences of mirror nuclei and stellar observables

The correlation between the charge radii differences in mirror nuclei pairs and the neutron skin thickness has been studied with the so-called finite range simple effective interaction over a wide mass region. The so far precisely measured charge radii difference data within their experimental uncertainty ranges in the 34Ar-34S, 36Ca-36S, 38Ca-38Ar, and 54Ni-54Fe mirror pairs are used to ascertain an upper limit for the slope parameter of the nuclear symmetry energy L & AP; 100 MeV. This limiting value of L is found to be consistent with the upper bound of the NICER PSR J0740+6620 constraint at 1 & sigma; level for the radius R1.4 of 1.4M0 neutron stars. The lower bound of the NICER R1.4 data constrains the lower limit of L to & AP;70 MeV. Within the range for L = 70-100 MeV the tidal deformability 1.4 constraint, which is extracted from the GW170817 event at 2 & sigma; level, and the recent PREX-2 and CREX data on the neutron skin thickness are discussed.

Automated summary

The correlation between charge radii differences in mirror nuclei pairs and neutron skin thickness was studied using a finite range simple effective interaction model. Precisely measured charge radii difference data in mirror pairs such as 34Ar-34S, 36Ca-36S, 38Ca-38Ar, and 54Ni-54Fe were used to determine an upper limit for the slope parameter of nuclear symmetry energy, L, at around 100 MeV. The upper limit of L was found to be consistent with the upper bound of the NICER PSR J0740+6620 constraint for the radius R1.4 of 1.4M0 neutron stars at the 1σ level. The lower bound of the NICER R1.4 data constrains the lower limit of L to approximately 70 MeV. The tidal deformability 1.4 constraint extracted from the GW170817 event at the 2σ level and recent PREX-2 and CREX data on neutron skin thickness are discussed within the range of L = 70-100 MeV.