In this report the role of Landau resonance between energetic electrons and plasmaspheric hiss waves at the inner radiation belt is investigated. These nearly structureless turbulent waves have been observed to exist at the inner belt over a large range of latitudes and to propagate with a wide distribution of wave normal angles relative to the geomagnetic field. For these waves, we show that at low L values, Landau resonance with electrons near their mirror points can give pitch angle diffusion coefficients larger than those expected for equivalent cyclotron resonances at the equator. Because of this fact, and because Landau resonance can occur at practically all electron energies that characterize this region (≤1 MeV), we suggest that this resonance may be regarded as the most important process to explain the enhancement in energetic electron precipitation at the inner belt, at least during the recovery phase of storms, when the plasmaspheric hiss population seems to be intensitied (i.e., Tsurutani et al., 1975). ¿ American Geophysical Union 1989 |