THE CALCULATION OF LINE POLARIZATION DUE TO SCATTERING BY ELECTRONS IN MULTI-SCATTERING AXISYMMETRICAL ENVELOPES

Previously we developed a numerical method to solve the continuum pola rized radiative transfer equation for the case of scattering by partic les with a Rayleigh phase matrix in axisymmetric geometries. Here we e xtend the method to compute polarized line profiles in stars with exte nded and expanding envelopes, but with the restriction that the polari zation in the line and continuum arises entirely from electron scatter ing. The method, extensively tested using Monte-Carlo calculations, tr eats optically thick lines, allows for extension of the line formation area relative to that of the continuum, and incorporates the frequenc y redistribution of photons caused by the thermal and bulk motions of the electrons. Test calculations are used to illustrate the effect tha t thermal broadening, line absorption, stratification, and inclination have on the emergent polarized line profile.