الفهرس 
Development of passive and active gamma/neutron technique for identification and quantification of radionuclides in different matrices
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Abstract
This thesis addresses the analysis, verification and quantification of uranium mass and enrichment of some ores and declared safeguarded nuclear materials (NMs) to the IAEA by using two non-destructive assays (NDA) methods: the passive gamma-ray assay and the active neutron interrogation by thermal neutron induced fission with measurement of the delayed gamma. Both techniques utilize high-resolution gamma spectroscopy based on an HPGe detector.The thesis deals also with applying different mathematical approaches to verify and purify the gamma line 185.71 keV of ²³⁵U from the probable contribution and overlapping due to the 186.21 keV of ²²⁶Ra.The thesis introduces also an innovative derived formula to calculate the ²³⁵U/²³⁸U activity ratio. The declared and safeguarded standard NMs samples were investigated using different NDA gamma spectrometers.The measured count rates ratio of Þ-lines; ²³⁵U/²³⁸U, ²³⁵U/²³⁴U, ²³⁴U/²³⁸U, ²³⁵U/²³⁶U and ²³⁶U/²³⁸U, were correlated with enrichment percentage (%E). A sharp correlation of % E and count rate ratio at the energy 84 KeV of ²³¹Th; the first daughter of²³⁵U, was found. Some samples were also analyzed by using (ICP-MS) for validation and found to be in agreement with gamma assay results