2000A&A...355.1168P

Refraction and polarization transfer in an ultrarelativistic highly magnetized pulsar plasma are considered. Normal waves in the pulsar plasma are linearly polarized however circular polarization arises in the polarization limiting region if radiation propagates at an angle to the plane of the magnetic field lines. The rays go off this plane due to refraction or (and) due to rotation of the magnetosphere. We found significant circular polarization of the outgoing radiation, in some cases with the sense reversal near the pulse centre. The frequency dependence of the circular polarization qualitatively resembles that observed. The swing of position angle of linear polarization is studied allowing for the wave propagation in the polarization-limiting region. The influence of refraction on the total-intensity profiles is examined as well. It is shown that refraction can provide the angular separation of emitted rays, so that the whole morphological classification of pulsar profiles can be explained within the frame of the primordial hollow-cone emission model taking into account wave propagation in the magnetosphere.