Abstract
The high-spin states of the nucleus 64Ge have been investigated using the GASP and the EUROBALL arrays of high-purity germanium detectors. In order to achieve the required experimental sensitivity, special selecting devices were used, namely a highly efficient array of liquid scintillators to detect neutrons and the ISIS Si-ball to detect light charged particles, which has been developed in the present work. A detailed decay scheme for 64Ge has been deduced, assigning spins and parities to the levels through a Directional Correlation from Oriented states analysis, an Angular Distribution analysis and a Polarization Correlation from Oriented states analysis. The character of an intense 1665 keV transition, previously reported as a stretched electric dipole with a small multipole mixing ratio, has been established as an electric dipole with a large multipole mixing ratio. The electric dipole strength has been measured using EUROBALL coupled to an early implementation of the EUCLIDES Si-ball and with the Koln plunger device, allowing an experimental estimate of the isospin mixing probability in 64Ge.