Internal Conversion Electrons Following Coulomb Excitation of Highly Deformed Nuclei

A study of internal conversion electrons following Coulomb excitation by alpha particles of a number of nuclei in the rare earth region has been made. In four cases, Eu¹⁵³, Ho¹⁶⁵, Lu¹⁷⁵, and Ta¹⁸¹, it was possible to obtain sufficient experimental data to make a fairly complete comparison with the predictions of the simple rotational model of Bohr and Mottelson. Within the large experimental uncertainties the data were consistent with the theory.First rotational state transitions have been studied in Gd¹⁵⁵, Gd¹⁵⁷, Re¹⁸⁵, Re¹⁸⁷, Ir¹⁹¹, and Ir¹⁹³. In addition transitions of 73 and 83 kev were observed in Ir¹⁹¹ and Ir¹⁹³, respectively. The data are consistent with the assignment of the transitions as coming from levels of these energies.