The 2002 IAEA intercomparison of software for low-level γ-ray spectrometry

The IAEA 2002 set of test spectra for low-level γ-ray spectrometry, reported on in a separate paper, was used in an intercomparison of widely available software packages, i.e. Anges 1.0, GammaVision 5.3, Gamma-W 1.68 for Windows, Ganaas 3.11, Genie2000 2.1, Hyperlab 2002.3.2.18, Interwinner 5.0 and UniSampo 1.97. With each program, efficiency curves were obtained for the two counting geometries (a 500 ml Marinelli beaker on a 33% relative efficiency HPGe detector, and a 100 ml pillbox on a 96.3% HPGe detector) and subsequently used to obtain radionuclide activities for the unknown samples. Both the calibration sources and the unknown samples contained radionuclides giving rise to cascade summing effects. Cascade summing correction factors as obtained with some of these programs, as well as with GESPECOR, were compared directly. the intercomparison meeting, the activities obtained were compared with the certified activities that had been kept secret until then. In this paper, the results will be presented and suggestions made for further improvement of the software.