الفهرس 
Gamma-ray Spectrometry
Digital Gamma SpectrometerOnly 14 pages are availabe for public view
 |  | from | 140 |  |  |
| | | from | 140 | | |
Abstract
Gamma spectrometers are very important nuclear measurement devices. They are mainly used in distinguishing the radioisotopes in the sample under test. Additionally, they can be used in determining the activities of these isotopes. The digital gamma spectrometer consists of a detector, a high voltage supply, a processing unit, a communication interface, and a PC. It isn’t easy for research and academic laboratories to have such devices due to their very high cost. There are a lot of research efforts in literature to develop low-cost processing units for gamma spectrometers. A lot of these efforts were based on FPGA chips. Recently, some research efforts are based on microcontroller chips due to their lower cost than the FPGA chips in addition to their advanced capabilities.
This dissertation presents two design proposals for low-cost digital gamma spectrometers: one is based on a Cortex-M3 microcontroller; and the other is based on a Cortex-M4 microcontroller. Three detectors are used to test the performance of the proposed designs. These detectors are a sodium iodide detector, a cesium iodide detector, and a high pure germanium detector. The Dissertation is arranged in four chapters as follows:
Chapter One: Introduction
This chapter introduces the concept and usage of gamma spectrometry. Then, the motivation of my dissertation is clarified followed by my contributions. Finally, the dissertation outline is presented.
Chapter Two: Digital Gamma Spectrometer
This chapter introduces digital gamma spectrometers with clarification of their block diagram, detectors, pulse processing algorithm, and performance metrics. This introduction gives the reader some basic information about gamma spectrometers. This chapter ends with a literature review of the developed low-cost gamma spectrometers’ processing units.
Chapter Three: Proposed Design of Low-Cost Digital Gamma Spectrometer
This chapter presents the proposed designs for gamma spectrometer using microcontrollers. The proposed designs are tested using three detectors: two scintillation detectors and one semiconductor detector. The output signal of each detector is characterized. Then, detailed descriptions of the proposed designs are presented.
Chapter Four: Experimental Setups and Results Discussion
The analog-to-digital converter (ADC) is the main component of the processing unit. Decreasing the sampling frequency of the ADC serves a lot in lowering the cost of the overall processing unit. This chapter starts by presenting an experimental investigation of the effect of decreasing the sampling frequency on the output resolution of the processing units. Then, the proposed designs in chapter three are tested to characterize their performance.