Simple model for decay of superdeformed nuclei - art. no. 051305

Recent theoretical investigations of the decay mechanism out of a superdefo rmed nuclear band have yielded qualitatively different results, depending o n the relative values of the relevant decay widths. We present a simple two -level model for the dynamics of the tunneling between the superdeformed an d normal-deformed bands, which treats decay and tunneling processes on an e qual footing. The previous theoretical results are shown to correspond to c oherent and incoherent limits of the full tunneling dynamics. Our model acc ounts for experimental data in both the A similar to 150 mass region, where the tunneling dynamics are coherent, and in the A similar to 190 mass regi on, where the tunneling dynamics are incoherent. [S0556-2813(99)50911-4].