Gamma-Ray Studies of ⁷¹Ge

Abstract

<p>The ⁶⁸Zn(α,nϒ) ⁷¹Ge reaction has been used to study the gamma decays of levels below 1.3MeV excitation in ⁷¹Ge. Gamma-ray angular distributions and angular correlations of gamma-gamma cascades were measured, using Ge(Li) detectors. The results were analysed using the compound Nucleus Statistical Reaction Model, to determine the angular momenta of most of the leveIs known in ⁷¹Ge below 1.3MeV, and the multipole mixing ratios of their gamma decays.</p> <p>The deduced level scheme has been compared with the predictions of a nuclear model calculation, in which the odd neutron in ⁷¹Ge is coupled to the collective quadrupole vibrations of the ⁷⁰Ge core. The model allowed for a pairing residual interaction between the core neutrons, and anharmonic terms in the core vibrations.</p>