INTERPRETATION OF THE FINE-STRUCTURE IN THE C-14 RADIOACTIVE DECAY OF RA-223

The experimental hindrance factors determined from the fine structure in the C-14 decay of Ra-223 are strikingly similar to the hindrance factors observed in the alpha decay of odd-A reflection-asymmetric deformed nuclei in spite of the deformed to spherical shape which occurs in the C-14 decay. Calculations of the overlap between the reflection-asymmetric ground state of Ra-223 and the spherical shell-model orbitals of Pb-209 involved in the C-14 decay are consistent with the experimental hindrance factors from the C-14 fine structure except that the j15/2 oribital is more strongly populated experimentally than the calculations suggest.