  Refraction of wave propagation in a corotating pulsar magnetospheric plasma
is considered as a possible interpretation for observed asymmetric pulse
profiles with multiple components. The pulsar radio emission produced inside
the magnetosphere propagates outward through the rotating magnetosphere,
subject to refraction by the intervening plasma that is spatially
inhomogeneous. Both effects of a relativistic distribution of the plasma and
rotation on wave propagation are considered. It is shown that refraction
coupled with rotation can produce asymmetric conal structures of the profile.
The differential refraction due to the rotation can cause the conal structures
to skew toward the rotation direction and lead to asymmetry in relative
intensities between the leading and trailing components. Both of these features
are potentially observable.
