Absorptive influence on interpretation of spatially resolved emission from apparently cylindrically symmetrical plasmas: A modeling approach

Spatial dissection of cylindrically symmetrical emitting plasmas using the Abel inversion is revisited. Effects of absorption, line shape, and continuum using classical formulations and formulae explicitly accounting for optical density are illustrated. Even with compensation for absorption, wavelength resolution must be narrower than spectral linewidth to obtain accurate profiles. The demands of adequate signal-to-noise ratio make such measurements on single discharges impossible, while signal averaging requires that all averaged discharges be positioned within a few micrometers spatially and stable within a few parts per thousand in intensity throughout the line profile. Even with understanding of the role of optical thickness, some spatial patterns well-known in the literature remain challenging to model. • Effect of spatially distributed absorption on Abel inversion demonstrated. • Wavelength resolution influence on observed absorption shown. • Compensation of absorption on computed radial profiles detailed. • Anomalies in literature Abel inversions partially explained.