Abstract
The full energy peak efficiency of HPGe detector is computed using a new analytical approach. The approach explains the effect of self-attenuation of the source matrix, the attenuation by the source container and the detector housing materials on the detector efficiency. The experimental calibration process was done using radioactive spherical sources containing aqueous (152) Eu radionuclide which produces photons with a wide range of energies from 121 up to 1408 keV. The comparison shows a good agreement between the measured and calculated efficiencies for the detector using spherical sources.