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We have developed a numerical method to solve the polarized radiative transfer equation for scattering by particles with a Rayleigh phase matrix in axisymmetric geometries. The method can treat an arbitrary number of scatterings, and provides a viable alternative to Monte-Carlo calculations for the computation of continuum polarization arising from Rayleigh scattering (or electron scattering) in axisymmetric envelopes. In the optically thin limit the computed polarization agrees with that predicted by the formula of Brown and McLean (1977, A\&A, 57, 141). For models in which multiple scattering is important, the results are in good agreement with that obtained from an independently developed Monte-Carlo code. Several test cases are used to highlight the significant influence of multiple scattering and the albedo on the observed polarization.
We have recently extended the method to compute polarized line profiles. The polarization in the line is assumed to arise solely from the effects of electron scattering. The redistribution of line photons over frequency space, due to electron motions (both thermal and bulk) is treated. Example profiles, computed with 2 independent codes, will be illustrated.
The polarization codes have immediate applicability to Be stars, Luminous Blue Variables, and Wolf-Rayet stars. We plan to use the codes to constrain the geometric properties of circumstellar matter, and as a probe of line formation.
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