Response functions of a germanium-sodium iodide detector system

Abstract

A gamma ray spectrometer is described which uses a lithium drifted germanium diode or sodium iodide crystal as a central detector in conjunction with an annular segmented sodium iodide assembly. The system can operate as a total absorption, anticoincidence, or pair spectrometer and individual detectors may be used separately. Thus, the requirements of high resolution or high efficiency gamma ray spectroscopy can be met by suitable choice of mode of operation. The various modes of operation are compared and typical results given to illustrate their performance at a variety of gamma ray energies. A detailed analysis is given of the response of 30 cm3 Ge(Li) detector for gamma rays up to 17.6 MeV.