An upper limit of ground-state energy fluctuations in nuclear masses

Abstract

Shell model calculations are employed to estimate an upper limit of statistical fluctuations in the nuclear ground-state energies. In order to mimic the presence of quantum chaos associated with neutron resonances at energies between 6 and 10MeV, calculations include random interactions in the upper shells. The upper bound for the energy fluctuations at mid-shell is shown to have the form sigma(A) approximate to 20 A(-1.34) MeV. This estimate is consistent with the mass errors found in large-shell model calculations along the N = 126 line, and with local mass error estimated using the Garvey-Kelson relations, all being smaller than 100keV. It agrees in both size and functional form with the fluctuations deduced independently from second-order perturbation theory.