Fluorescence-based method for estimating the dead layer thickness of a broad-energy germanium detector

摘要

A fluorescence-based method is proposed in this paper to estimate the front dead layer thickness of a broad-energy germanium detector. The germanium fluorescence was induced by the ~(57)Co 14.4 keV gamma radiation incident on the dead layer. The count ratio between germanium fluorescence and the transmitted probe photons was experimentally measured and then compared with a series of Geant4 calculations for thickness determination. The method is sensitive to dead layer thickness owing to direct measurement of the thickness-dependent fluorescence and is independent of probe intensity and materials intervened between the source and the detector by using count ratio. The approach is anticipated to have a general application to surface studies of various types of germanium detectors.