Badawi M.S., Gouda M.M., El-Khatib A.M., Nafee S.S., El-Mallah E.A.
NEW ANALYTICAL APPROACH TO CALIBRATE CYLINDRICAL HPGE DETECTOR INCLUDING CORRECTIONS FOR SELF ATTENUATION OF LARGE CYLINDRICAL SOURCES AND ATTENUATION OF ALL DETECTOR HOUSING MATERIALS ^{[№ 5 ' 2013]}
HPGe semiconductor detectors are very useful for radioactivity measurement and to calculate the absolute activity, the full energy peak efficiency of the detector is needed. In this work, to calibrate the co-axial HPGe semiconductor detector, we introduce a new theoretical approach based on the Direct Statistical method proposed by Selim and Abbas to calculate the full-energy peak efficiency for cylindrical detectors. The present method depends on the accurate analytical calculation of the average path length covered by the photon inside the detector active volume and the geometrical solid angle, Щ, to obtain a simple formula for the efficiency. In addition, self attenuation of source matrix (with radius greater than the radius of the detector), the attenuation by the source container and the detector housing materials are also treated by calculating the average path length cross these materials. 152 Eu aqueous sources covering the energy range from 121 up to 1 408 keV were used. Remarkable agreement between the measured and the calculated efficiencies is achieved with discrepancies less than 2 %.