Resonant transformation of wave polarization due to plasma nonuniformity

When a transverse electric wave is incident on a plasma column with an axial density gradient, the resultant scattered field is not purely transverse electric, but also has a transverse magnetic component. The relative importance of the latter is strongly enhanced at the main resonance of the plasma cylinder, its absolute magnitude becoming great even for moderate values of the axial density gradient. The present study is limited to a perturbation analysis of the effect. The inclusion of this effect leads to a much closer agreement between theory and experiment in the positive column of a discharge than was the case for a previous theory which only accounted for transverse electric to transverse magnetic transformation due to plasma axial drift along the column.