Direct Mathematical Calculations for Total and Full -energy Peak Efficiencies of Well-type Gamma-ray Detectors

Abstract

Most radioactive sources produce gamma rays of various energies and intensities. When these emissions are collected and analyzed with a gamma-ray spectroscopy system, a gamma-ray spectrum can be produced. A detailed analysis of this spectrum is typically used to determine the identity and quantity of the gamma emitters present in the source.A gamma spectroscopy system consists of a detector, electronics to collect and process the signals produced by the detector, and a computer with processing software to generate, display, and save the spectrum. Other components, such as rate meters and peak position stabilizers may also be included. Gamma spectroscopy detectors are passive materials that wait for gamma interaction to occur in the detector volume. The most important interaction mechanisms are the photoelectric effect, the Compton Effect and pair production.In our work, we used the straightforward analytical formulae for the computation of the well-type detector efficiencies. The well-type detector consists of a crystal detector with a cavity drilled at the center. For example, a cavity of 15mm diameter may be drilled into the center of a 75-mm-diameter cylindrical crystal. This detector geometry was designed in the early years of solid scintillation analysis and used by the author in the early 1960s. The well-type detector was envisaged with the objective of surrounding the sample with detector as much as possible. This type of detector is widely used and has proved a powerful tool, particularly when low activity, small volume samples are to be analyzed by gamma-ray spectrometry.This thesis contains three chapters and an Appendix

Student(s)

Samer Hassan Akl

Supervisor(s)

Prof. Mahmoud Korek, Prof.Mahmoud Abbas