The Mode-Separated Pulse Profiles of Pulsar Radio Emission

Abstract Two modes of orthogonal polarization are generally observed in the radio emission from pulsars. Essentially all attempts to calculate the average profiles of the individual modes have assumed that the modes occur separately. We have presented evidence, however, that the modes occur simultaneously. Therefore, we believe that “mode-separated” pulse profiles which have been published to date reveal little about the polarization properties of the individual modes. Calculating mode-separated pulse profiles for superposed orthogonal modes is complicated by the unknown polarization properties of the individual modes. However, the simplest model of pulsar radio emission which can explain the wide variety in the emission’s polarization is one in which the individual modes are completely polarized. We use our simple model to compute the average profiles of the orthogonal modes in PSR B0525+21. The total intensity of the two mode profiles resembles the overall pulse profile, and each profile is highly linearly polarized.