Correlations between charge radii differences of mirror nuclei and stellar observables

Abstract: 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 $\approx$ 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 R${1.4}$ of 1.4 M$\odot$ neutron stars. The lower bound of the NICER R$_{1.4}$ data constrains the lower limit of L to $\approx$ 70 MeV. Within the range for L = 70-100 MeV the tidal deformability $\Lambda^{1.4}$ 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.