Habilitation a Diriger des Recherches : Caractérisation par spectroscopie d'émission des plasmas de bord des machines de fusion parconfinement magnétique
This manuscript describes some spectroscopic techniques applied to magnetic fusion plasmas. These techniques are based on the use of spectral lines which are affected by Stark and Doppler broadenings and by level-splitting Zeeman effect and allow the determination of the plasma parameters of the emissive plasma. The plasma conditions considered here cover all plasma regimes met in tokamak and stellarator divertors ranging from ionizing (low density, attached plasmas) to recombining plasmas (high-density plasmas detached plasmas). The analysis of the Balmer-alpha of hydrogen and deuterium allow the determination of the neutral sources, the population densities and temperatures of the co-existing neutral classes as well as their fractions. Such parameters are useful for particle recycling evaluation. Being very sensitive to Stark broadening, H/D high-n Balmer lines observed under detachment conditions of divertors are used to determine the electron density of such plasmas. Spectra of lines emitted by carbon impurities from the divertor of JT-60U tokamak under detachment conditions with the presence of an X-point MARFE were also analysed to determine the spatial distribution of the electron density of the divertor plasma. The last application considered here concerns the spectroscopic study of the ablation cloud of a carbon pellet injected in the Large Helical Device (LHD) with a particular focus on the analysis of a C II line affected by Stark broadening.Ce manuscrit décrit quelques techniques spectroscopiques appliquées aux plasmas de fusion magnétique. Elles sont basées sur l'utilisation de spectres de raies qui sont affectées par les élargissements Stark et Doppler et par l'effet Zeeman et permettent de déterminer les paramètres des plasmas émissifs