الفهرس 
Theoretical background and literature reviewOnly 14 pages are availabe for public view
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Abstract
The main objectives of this work are: Study the characteristics and the factors affecting the registration efficiency of CR-39 and DAM-ADC detectors in order to reduce etching time through etching process using new chemical etching condition. Registration of proton tracks in short etching time by using a new etching condition. Establishment the calibration factor for this radon dosimeter, it was used in measurement of the annual effective dose.
In order to achieve these, the thesis is composed of three chapters:
Chapter 1:
In this chapter, theoretical background is given to support the technical and experimental part of this work. It is includes the operation of solid state nuclear track detector, theoretical criteria for track formation, etching parameters that govern the track formation which are the bulk etch rate VB , the track etch rate VT, Sensitivity, Critical angle, Etching and registration efficiency. Theoretical review, for registration of fast neutron and radon measurements. Finally, literature review.
Chapter 2:
Describe the preparation of detectors, radioactive sources such as Am241, 252Cf and Am-Be source, experimental set up, radon calibration chamber, AB-5 monitor, DTA and DSC.
Chapter 3:
It contains experimental work and discussion of obtained data, characteristics studies for fast detection of alpha particles in CR-39 were investigated by using a new etching condition (8 ml of 10N NaOH+ 1 ml CH3OH) at 60°C for 45 min. The major advantage of the present method in this work is that CR-39 detectors are successfully used in the detection of alpha particle in short duration time (45 min) with VB= 2.73μm/h with considerable efficiency. The sensitivity, critical angle and etching efficiency has been studied. The activation energy (EB) of the bulk etching rate for the CR-39 sheets was also calculated and presented, moreover, track activation energy, ET has found to be lower than the bulk activation energy, EB for CR-39 detectors. (EB=0.881 eV, ET=0.718 eV)
The best chemical etching condition for fast detection of alpha particles through DAM-ADC detector is (8 ml of 10N NaOH + 1 ml CH3OH) for 60 min. The major advantage of the present method in this work is that DAM-ADC detectors are successfully used in the detection of alpha particle with low energy in short duration time (60 min) with VB= 8.52 μm/h with considerable efficiency. The sensitivity, critical angle and etching efficiency has been studied. The activation energies of this etchant have been calculated. Moreover, track activation energy, ET, has been found to be lower than the bulk activation energy, EB, for the DAM-ADC nuclear track detectors. (EB=0.644 eV, ET=0.573 eV). DAM-ADC can be used in the field of radon gas measurement and detection of fission fragment in short time.
For application of using CR-39 and DAM-ADC detectors, Detection of recoil atoms due to the fast neutron impact with hydrocarbon material (CR-39 and DAM-ADC material) were investigated by using new etching conditions, also the experimental track density has been compared with values of track density obtained by previous optimum etching condition, i.e. (6.25 N NaOH solution at 70 ˚C for 9 h); it is found that the track density improved using our new etching conditions in the case of CR-39 detector. Detection efficiency have been calculated and found to be constant with neutron fluence, which reflects the importance of using CR-39 and DAM-ADC detectors in the field of neutron dosimetry. In the case of DAM-ADC detector, further experimental investigation is required to improve the response and increase the detection efficiency.
A radon chamber is designed and constructed to control on samples moving, flow of radon, temperature and humidity. The constructed radon chamber was tested and calibrated with radium sources, after that, radon half-life time inside the constructed chamber was calculated experimentally, finally, average value of calibration factor of CR-39 detector through 5days was established in this study and found to be 0.187 (track cm-2 d-1/Bq m-3) at 20 0C irradiation temperature. Comparison between the experimental values of calibration factor and previous published values, a good agreement was obtained through this comparison.