Using the experimental method for the computation of the efficiency in various measurement geometries for a reference point source geometry with NaI(Tl) Detectors

Abstract

The quality of the results of gamma spectrometry measurement depends directly on the accuracy of the detection efficiency in the specific configuration of concern. In the present work, measurement conditions .In gamma-ray spectroscopy using Scintillation detectors, one usually needs to know the full-energy peak efficiency for any specific source-detector we will describe the experimental method employed to calibrate Scintillation detectors at the laboratory of Dr.Younis. S. Selim of Radiation PhysicsFaculty of Science - Alexandria University, where the detectors are calibrated for measuring point sources are placed in succession at constant distance from the considered detector to optimize the detection. Experimental efficiency calibration is restricted to several measurement geometries and cannot be applied directly to all measurement configurations. An alternative possibility of being able to compute the efficiencies is thus highly desirable. The purpose of this work is to Calibration The NaI(Tl) scintillation detector practically by using radioactive point sources in the development of axial dimensions from the surface of detector and with varying photon energies