Accounting for incomplete charge collection in Monte Carlo simulations of the efficiency of well-type Ge-detectors

The influence of the process of incomplete charge collection on the performance properties of HPGe well-type detectors is studied. A simplified sub-routine, that takes into account the total collection time of charges within the Ge-crystal, has been developed and coupled to the Monte Carlo photopeak efficiency. Only the manufacturer's data of the detector's geometry and the detector's operating voltage was used in the sub-routine. The corrected photopeak efficiency simulations, as based on this new sub-routine, showed much better agreement with the experimental data, especially for energies above 40 keV. The ratio between the experimental and simulated efficiency at 1460 keV were, for example, improved from 0.73 to 0.96 after performing these corrections on our largest well-type Ge-detector. (C) 2002 Elsevier Science B.V. All rights reserved.