Guidance of whistler‐mode waves through the plasmasphere

Using appropriate plasmaspheric models, whistler‐mode wave propagation has been studied. It is shown that the ray curvature of propagating whistler‐mode waves is quite different from the geomagnetic field curvature. The presence of field‐aligned irregularities superposed on various models of ambient plasmaspheric electron density introduces the compatibility of ray and field curvatures. The presence of field‐aligned irregularities and modified refractive index has been used to study the guidance of whistler‐mode waves along the field line. The critical angle of elevation, track width, and electron density gradient needed for guidance of whistler waves have been computed. Using modified refractive index, the propagation time of whistlers has been computed. It is argued that the analyses of whistler sonograms accounting for some of these features would result in a useful diagnostic.