Calculation Of Full-energy Peak Efficiency Research Articles

HPGe detector full-energy peak efficiency calculation for inhomogeneously activated samples

We present and evaluate a program for the semi-empirical calculation of the full-energy peak efficiency of a hyper-pure germanium detector, by using the efficiency transfer method. Using simple Monte-Carlo integration and constructive solid geometry, we are able to calculate the effective solid angle for a wide range of HPGe detector and sample geometries. However, the main advancement is including in our calculations the inhomogeneity of the sample activity, caused by the inhomogeneous neutron flux when performing neutron activation analysis (NAA). This reduces systematic error in the standard procedure of NAA. To increase usability, the input and output file formats used are compatible with the program SOLANG, which belongs to the Kayzero for Windows (KayWin®) software.

Experimental verification of mathematical efficiency modeling and true coincidence summing correction of the SAGe Well detector

The characterization and ray-tracing algorithm in ISOCS/LabSOCS has been extended to calculate full energy peak and total efficiencies for the Small Anode Germanium Well detector. The extension allows for true coincidence summing correction using the standard algorithm in the Genie 2000 software. The accuracy of the full energy peak efficiency calculation and the coincidence summing correction has been experimentally validated to be the same as for non-well detectors.

Calculation of full-energy peak efficiency of NaI (Tl) detectors by new analytical approach for parallelepiped sources

Abstract A new analytical approach is presented for the calculation of full-energy peak (FEP) efficiency of NaI (Tl) detectors. The self-attenuation of the parallelepiped source matrix, the attenuation by the source container, and the detector housing materials were considered in the mathematical treatment. The efficiency values calculated using the presently suggested analytical approach are compared with those measured values obtained by two different sizes of NaI (Tl) detectors. The calculated and the measured full-energy peak efficiency values were in a good agreement.

An accurate method for the determination of 226Ra activity concentrations in soil

A quantitative method to determine the activity concentration of 226Ra in soil samples was established using high performance environmental gamma-ray spectrometry. In this method, a semi-empirical calibration procedure was developed for full energy peak efficiency calculation utilizing the elemental composition of the soil sample. Aatami software was used to deconvolute the 235U and 226Ra doublet at 185.7 keV and 186.2 keV, respectively, and to fit the baseline of the soil gamma-spectrum for the determination of 226Ra activity. The results indicated that the Aatami doublet deconvolution procedure provides a rapid and accurate analysis of a complicated spectrum in comparison with other cumbersome spectral interference correction methods. The study also compared the results with those obtained by radon progeny (214Pb, or 214Bi) measurements and found that the deconvolution method provided a more accurate 226Ra activity as it is independent of the error caused by radon diffusion. This error can be quite large since the amount of escaped radon gas through the sample container walls and sealing cannot be accurately quantified.