Analytic formula for B(E2) values in even-even nuclei with A>60

An approximate analytic formula for calculating B(E22+1-->0+1) transition probabilities is proposed. We show that this formula reproduces quite accurately numerical calculations based on the interacting-boson model (IBM), and experimental data for a large number of nuclei from Zn to Pt, and in the actinide region, the largest discrepancies being of the order of 40%. The analytic relation is based on an IBM Hamiltonian, whose four parameters can be estimated using expressions given in the text. Since these expressions are based on a microscopic shell-model description, the formula only requires knowledge of the (N,Z) values of the isotope in question.