Influence of the boundary layer of a shockheated plasma on the Stark profiles of the Al(I) resonance lines.
Abstract
The influence of temperature and density gradients in the boundary layer of an Al(CH3)3seeded shockheated plasma on the Stark profiles of the Al(I) resonance lines 3961.5 A and 3944 A is investigated by solving the radiative transfer equation. The thermal boundary layer thickness is varied from 0 to 1 cm, assuming complete local thermodynamic equilibrium (LTE) throughout the inhomogeneous region. The calculations show that the line profiles are distorted. For the plasma conditions of an experiment, it is shown that reabsorption diminishes the intensity and displaces the maxima of the profiles of both resonance lines in the same relative proportions. Thus, the ratios of their halfwidths and of their shifts are practically independent of the boundarylayer effect. It is concluded, therefore, that the measured difference of the halfwidths of the Al(I) resonance doublet must be an intrinsic plasma effect.
 Publication:

Journal of Quantitative Spectroscopy and Radiative Transfer
 Pub Date:
 October 1979
 DOI:
 10.1016/00224073(79)90075X
 Bibcode:
 1979JQSRT..22..389T
 Keywords:

 Aluminum;
 Boundary Layer Plasmas;
 Line Spectra;
 Plasma Heating;
 Shock Heating;
 Stark Effect;
 Optical Resonance;
 Optical Thickness;
 Radiative Transfer;
 Spectral Line Width;
 Temperature Gradients;
 Thermodynamic Equilibrium;
 Plasma Physics;
 Physics