Energy linearity of high-purity germanium detectors in the region of the GeK-absorption edge: experimental results

Non-linearities in the energy response of gas detectors in the regions of t he absorption edges of the detection medium are well documented. Monte Carl o calculations show that the non-linearity results from differences in effi ciencies for converting absorbed radiation into ionisation for different at omic sub-shells. Energy non-linearity in germanium-based solid-state detect ors in the region of the germanium 11.104-keV K-edge is not well documented , although a 1% non-linearity has been previously reported in a Ge(Li) dete ctor. This relatively high value is of practical concern since high-purity germanium (HPGe) is often the detector of choice for alpha- and X-ray spect rometry down to a few keV. In this paper, we present the experimental resul ts for the energy response of a HPGe detector in the 8-15-keV energy region of the germanium K-edge. Within the accuracy of our measurements, we concl ude that there is no measurable non-linearity effect in germanium at the K- edge. (C) 2000 Elsevier Science Ltd. All rights reserved.