Measurements of electron density and temperature of helium plasmas in a cw running magnetic multipole plasma source by repetitively laser-pulsed 90° Thomson scattering are reported. This is the first experiment in which this technique has been applied to such plasmas. Measurements are performed at a helium gas pressure of pg = 5 Pa, the discharge voltage was Ud = 100 V, the discharge current was 5 A ≤ Id ≤ 30 A, and the cathode heating current was 80 A ≤ Ih ≤ 140 A. Electron energy distribution functions obtained from the Thomson scattering spectra are studied. The obtained plasma parameters are electron temperature 1.5 eV ≤ kTe ≤ 5 eV and density 1012 cm−3 ≤ ne ≤ 4 × 1012 cm−3, respectively. The sensitivity of detection of the experiment is in the range of 109 electrons and the accuracy of the electron temperature and electron density are specified to 15% and 20%, respectively. In addition, the neutral density and helium gas temperature are obtained from the Rayleigh component of the scattered spectra. Langmuir probe measurements are performed under the same plasma conditions and a comparison of the results with Thomson scattering shows good agreement between the two diagnostics.

In this paper, we present an experimental and theoretical study of pulse laser ablation of stainless steel target. Various parameters, such as laser power, pulse duration, enthalpy and heat capacity are used. The evaluation of which software will be suitable for the ablation processes has been done. The possibility to find micro-craters and microdefects was noted by using Reflection Optical Microscope (ROM). The ablation process induced by lasers is a collective phenomenon: that basically involves two phenomena: the laser radiation-with matter interaction and the dynamic of the ablation process. Only the solid-liquid phase change is considered. This study contributes to a better understanding of the physical process involved in the laser ablation targets

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