A Quick Method to Calculate NaI(Tl) Detector Efficiency Depending on Gamma ray Energy and Source-to-detector Distance

This paper examines and presents a simple computational Monte Carlo algorithm to determine the total, intrinsic and geometric efficiencies of NaI(Tl) gamma ray detectors for gamma rays emitted by isotropic radiating (point) sources with several energies in the range of 150-3000 keV. The code was used to compute efficiency values for various source-to-detector distances for each studied gamma ray energy. The comparisons with the data reported in the literature indicated that the present algorithm is useful in efficiency calculations for any source-detector and geometry configuration.

Keywords:

Gamma ray, Detection, Total efficiency Intrinsic efficiency, Geometric efficiency, Monte Carlo,

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