6533b82bfe1ef96bd128d52f

RESEARCH PRODUCT

Fabry–Pérot lineshape analysis in an optically thick expanding plasma

subject

description

In this work the authors present Fabry–Perot measurements of Ar atom spectral line profiles originating from the expansion of an Ar–N2 thermal plasma into a low pressure environment. The plasma is characterized by strong density, temperature and velocity gradients and it offers a high degree of light absorption for some gas mixtures. First, it is demonstrated that the Abel inversion method cannot be applied under such conditions even if absorption is absent. Second, two approaches are examined to obtain plasma parameters in the case of an optically thick expanding plasma. It is shown that velocity and temperature development along the jet radius can be inferred from experimental lineshapes when radiation production and absorption are taken into account in the core and in the surroundings of the jet.