الفهرس 
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Abstract
The aim objective of this thesis is the study and design of a suitable plasma medium used for particle acceleration. The study reveals that the present plasma can performs plasma wakefields of high gradient in the range of MeV and this wakefield increases with the increase of the discharge pressure. In addition, the choice of that audio frequency at this particular high pressure (≈ 0.2 Torr.) performs highly adapted conditions for the production of high gradient wakefield.
The detected output plasma particles predicts the acceleration of injected ions reaching an energy range exceeding 1 MeV without applying an extracting voltage. Experimental data using computer simulation SRIM expect an energy gain from 4 to 18 MeV.
The present study of a single plasma cell points to the possibility of constructing a long accelerating tube composed from multi-cells to act like drift tubes in the linear accelerator.
Our study is concentrated in the characteristics and diagnosis of one cell (L=27 cm, = 4cm).
The thesis is composed of five chapters in addition to this summary and conclusion.
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The first chapter represents a theoretical review of the particle acceleration technique.
The second chapter deals with the plasma accelerators
The third chapter deals with the plasma waves and the effect of electron beam injection on the plasma medium.
The forth chapter comprises the experimental setup for the creation of the plasma inside a Pyrex column of 27 cm long and 4 cm diameter, in addition, a description of the measuring techniques is performed.
The last chapter presents the experimental results and discussions of the plasma medium characteristics and the influence of electrons or ions injection on the plasma column.
In this work, plasma medium is created with an audio power in the audio range 10 kHz at pressure 0.2 Torr.
The plasma is created by using nitrogen and argon gases in order to study the different behaviors that characterize the plasma medium.
The plasma density and the electron temperature were determined using a double Langmuir probe. It was found that the electron plasma density increases in the presence of the electron
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injection from the range of (0.39 – 1.75) x1012 cm-3 to the range of (0.5 – 1.06) x1013cm-3 for the Ar gas while for the N2 gas it increases from (0.35 – 5.3) x1012 cm-3 to (0.2 – 6.5) x1012 cm-3 along the plasma length.
Electrons have been injected into the plasma cell from a tungsten filament that delivers a power up to 70 Watt, in order to study its influence on the plasma diagnostics.
In addition, aluminum and tungsten ions are ejected into the plasma cell from an electrode called emitter to experiment their behavior in the plasma and the effect of the latter on them.
Linear and deviating plasma glowing tube of the gas discharge are used for metal deposition, to experiment the produced plasma electric and magnetic fields that interact in turn and influence the motion of electrons and heavy ions from electrode to electrode displacement.
A second tube is connected to the plasma tube including the target, an ion track detector CR-39 is used to detect the accelerated particles from Aluminum and tungsten electrode.
After two hours of operation for each aluminum and tungsten electrode, a deposited agglomerations of aluminum and tungsten are found on CR-39 surface. These ions are transported from the plasma through a tube in a field free region mode to reach the detector. The
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etching process of CR-39 shows a track range for the aluminum ions
reaching 6.1 m while for the tungsten it reaches 7.78 m. SRIM
code shows that these ranges corresponding to energy ranges from
4-18 Mev. Another indication of the possibility to obtain high
energy from the plasma accelerating field is by calculating
E0 [V/cm] _~ 0.96 2 / 1
0n [cm-3] where n0 = 5 x 1012 cm-3, one can find
that E0 = 2 x 106 v/cm. These results indicate that ions reaching the
detector by traversing the plasma gain larger energy than the initial
AF energy applied.
Keywords: Audio Plasma/SEM/XRF/EDX/CR-39/ Langmuir probe
/Acceleration/ electron density/ Wakefield/ Etching/ Tracks/