Use of ge(Li) detectors in γ-γ coincidence experiments

Large volume Ge(Li) detectors have been used in a γ-γ coincidence arrangement employing two Ge(Li) detectors. The first part of this paper reports the results of studies of the timing properties of planar and coaxial diodes and the time resolution curves that can be obtained. For two cylindrical coaxial diodes the full-width at half-maximum of the time resolution curve was 14 nsec for 511 keV γ-rays. The second part of the paper describes the application of the detectors in γ-γ coincidence experiments. The coincidence counting rates are limited by the total singles counting rates that can be tolerated without excessive loss of energy resolution. Results are shown illustrating the application of a Ge(Li)-Ge(Li) coincidence arrangement to a complex γ-ray spectrum and the ability of this technique to reveal new information on γ-γ cascades.