HIGH-K BARRIER PENETRATION IN HF-174 - A CHALLENGE TO K-SELECTION

A sensitive study of the decay of the deformation-aligned K=14, 4s isomer in Hf174 has revealed a multitude of the K-forbidden branches to the ground-state rotational band and other low-K bands, in competition with the known decays to high-K bands. The isomeric transitions have consistently low hindrance factors. These anomalous findings in an axially symmetric deformed nucleus severely test our understanding of the K-selection rule. The isomeric decay to an I=12 rotation-aligned state, and its mixing with the I=12 yrast state, provide a partial explanation. © 1990 The American Physical Society.