RESUMO
The precision measurements of U3O8 and Ra(eU3O8) concentrations were evaluated in 23 geological rock samples by high resolution gamma ray spectrometry (HPGe) using two P-type HPGe detectors. The use of Detector 2 (DET2) (GC5019) has increased the sensitivity by a factor of two for both the measurements in comparison to Detector 1 (DET1) (GCD30180). The Minimum Detection Limit (MDL) and Limit of quantification (LOQ) for U3O8 in DET2 has increased significantly because of negligible background counts in 1.001 MeV Ï energy peak (0.838% gamma yield). The MDL for Ra(eU3O8) measured by 0.609 MeV and 1.760 MeV has not improved significantly due to the high background counts in these energies whereas LOQ has improved appreciably. DET 2 has given higher level of confidence in reporting the analytical results with acceptable repeatability due to the decrease in uncertainty of the measurements.