The excited states in the odd-odd 124I nucleus produced by the (p,n) reaction

Abstract

Gamma spectra produced in the 124Te(p, n) 124I reaction were taken as a function of proton bombarding energy E p = 3.9 MeV to 6.0 MeV. A level scheme composed of 40 excited states was constructed on the basis of singles γ-spectra and extensive γ-γ coincidence measurements. The coincidence measurements were carried out utilizing a three-parameter Ge(Li)-Ge(Li) timing system. The mean lifetimes of the first two excited states 55.5 and 123 keV were determined, respectively, as 74.5(75) and 13.9(15) ns. Angular distribution measurements combined with the results from the coincidence counting rates enabled some spin and parity assignments to be made. The structure of the states was discussed on the basis of a de-excitation mode comparison with the corresponding levels in the neighbouring odd-odd nucleus 122Sb.