الفهرس 
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Abstract
Laser-induced plasma spectroscopy(LIPS) or LIBS (the acronymof Laser wn Spectroscopy)isanopticaldiagnostic technique based on emissionspec ombines all therequired processesfor atomic spectrometry: sample vapion,excitationand ionization, simultaneously.The principle is to focus a laserpower onto the sample (solid,liquid,gasor aerosol)to be analyzed to create apot. The material in the sample is excited in the hot plasma and its spectral emlyzedin order to identify and quantify its elemental composition by usinopy in the UV-visible or near-infrared.ndeed, LIBS isconsidered as a powerful real-time and in-situelemental analysis tntly has become a very popular and well-established method for rapid qualitive analysis of materials. In respect to stability, reliability and versatilitye reveal the tendency for developing the key components (laser sources, spect, analytical chambers) used in differentLIBS applications.This dissertation was set forthto evaluate the potential of a fast growing laser teclaser, as source of light in the field of laser-induced breakdown spectroscopympact fiber lasers are nowavailable, which produce a high quality beam ant energy to generate opticallyinteresting plasmas for analytical purposes at vn rates.The study began with the diagnostics of the fiberlaser-induced plasma. Plasma ptemperature, electron number density and temporal behavior of the emissionlited in air at atmospheric pressure and at constant laser fluence for laser pulsefrom 40 to 200 ns. The emission linesand the plasma parameters were deduced the duration range via spectroscopic analysis and inspection of the producedore, the influence of laser irradiance in term of pulse duration variationd.Subsequently, byusing the same pulse duration range and keeping the laser fluenceconstant, we are committed toevaluate and examine, using gated and non-gated analysis, the analytical performancesof this laser source in terms of calibration curves (sensitivity andnonlinearity) and limits of detections (LOD) in the low µg g-1range for the minor elements (Mg,Si, Cu) in the aluminum alloy samples. The experiments werecarried out by usingtwo differentspectrometers,Benchtop Czerny–Turner spectrometer/intensified CCDfor gated analysis and compact fiber-optic-coupled symmetric crossed Czerny-Turner spectrometer/linear array detectorfor non-gated analysis.In order to draw the complete picture about the potential usefulness for using this laser, the effect of both target properties and laser parameter(i.e. the corresponding pulse duration range)on he ablation behaviorof the fiberlaser was studistudiedthrough the determination the fluence thresholds for some pure metals having different thermophysical properties. The measurements were deduced for the plasma formation thresholds which is called laser-induced breakdown thresholds and for theaser ablation thresholds.