Comparison between Pc‐1 pulsation propagation paths and the whistler determined plasmapause

Abstract

Observations of structured Pc‐1 pulsations at Siple Station, Antarctica allow comparison of the propagation paths of these signals with previously reported whistler observations. The whistler data have provided a detailed history of the plasmapause location during a six day interval of magnetic disturbance and recovery. Determination of the equatorial distances to the propagation paths of the Pc‐1 signals by dispersion analysis indicates that the hydromagnetic whistlers propagate 1 to 4 R e above the plasmapause. We find, however, that structured Pc‐1 signals are observed only when the plasmapause is near or above the Siple field lines. This suggests that the Pc‐1 signals are propagating in or below the plasmapause and that some of the assumptions of the dispersion analysis may be in error.