Automated efficiency calibration of HPGe spectrometers for in-vitro soil samples

A method of automatically generating an efficiency calibration for a given HPGe spectrometer based upon the density of the soil sample being analyzed is described. This is accomplished by means of a computer program that generates a least-squares fit of the spectrometer’s intrinsic efficiency as a function of both γ-ray energy and sample density. Once this three-dimensional model for a spectrometer’s intrinsic peak efficiency has been produced, it can then be used to automatically generate the intrinsic peak calibration curve for that spectrometer based upon the density of the soil sample to be analyzed. The computer program will then use the newly generated intrinsic peak efficiency calibration curve to calculate the peak activities for the spectrum file specified by the user.