Cross correlation of low-lying levels of even–even nuclei

Abstract

We consider the cross correlations of low-lying energy levels of nuclei belonging to small intervals of the excitation-energy ratio R 4 / 2 of the first 4 + to 2 + states. The mean value of the cross-correlation coefficients, plotted as a function of R 4 / 2 has deep minima at values of R 4 / 2 = 2.2 and 2.9, which correspond to the critical dynamical symmetries of the interacting Boson model. The distribution of the calculated coefficients for nuclei belonging to different R 4 / 2 classes has different pattern.