Observations of pulsar radio emission. II - Polarization of individual pulses

Observations of complete polarization characteristics of individual pulses in the frequency range from 110 to 450 MHz are reported for twelve pulsars along with the linear polarization characteristics at 1400 MHz for four pulsars. Subpulses were found to be mostly linearly polarized, with the variation of position angle within a subpulse usually less than 30 deg. In many pulsars at low frequencies the position angle of successive subpulses is stable for most of the profile. For certain components, however, subpulses are observed with position angle orthogonal to the most common angle. An interpretation based on self-absorption in the emission region is given.