Systematics of B(E2;01+→21+) values for even-even nuclei

Abstract

We have completed a compilation of experimental results for the electric quadrupole transition probability B(E2)↑ between the $0^{+}$ ground state and the first $2^{+}$ state in even-even nuclei. The adopted B(E2)↑ values have been employed to test the various systematic, empirical, and theoretical relationships proposed by several authors (Grodzins, Bohr and Mottelson, Wang et al., Ross and Bhaduri, Patnaik et al., Hamamoto, Casten, Möller and Nix, and Kumar) on a global, local, or regional basis. These systematics offer methods for making reasonable predictions of unmeasured B(E2) values. For nuclei away from closed shells, the SU(3) limit of the intermediate boson approximation implies that the B(E2)↑ values are proportional to ($e_{\mathrm{p}{N}_{\mathrm{p}+e_{\mathrm{n}{N}_{\mathrm{n}{)}^2}}}}$, where $e_{\mathrm{p}(e_{\mathrm{n}}}$) is the proton (neutron) effective charge and $N_{\mathrm{p}}$ ($N_{\mathrm{n}}$) refers to the number of valence protons (neutrons). This proportionality is consistent with the observed behavior of B(E2)↑ vs $N_{\mathrm{p}{N}_{\mathrm{n}}}$. For deformed nuclei and the actinides, the B(E2)↑ values calculated in a schematic single-particle ‘‘SU(3)’’ simulation or large single-j simulation of major shells successfully reproduce not only the empirical variation of the B(E2)↑ values but also the observed saturation of these values when plotted against $N_{\mathrm{p}{N}_{\mathrm{n}}}$. .AE