The influence of the twist effect of the magnetic field on the pulsar radio emission polarization.

The relationship between magnetic dipole radiation and the magnetic field distortion is analyzed within the framework of the 'polar cap' model of a spinning neutron star. The speed by which the magnetic field-line cone is twisted relative to the undisturbed dipole field was calculated. It is shown that the twist of the cone will make the curve for the linear polarization angle phi_p(Theta) asymmetric with respect to longitude in the averaged radio-pulse profile. Phi_p(Theta) is shifted away from the center toward the leading edge of the profile, becoming steeper with distance from the star. Comparison with polarimetric data for neutron stars showed that the shift was related to the pulsar period and the radio frequency. Radio emission heights were calculated for the magnetospheres of pulsars 0833 - 45; 1929 + 10; and 0628 28 on the basis of the above relation. A list of the emission heights is given.