LOWER-HYBRID COLLAPSE, CAVITON TURBULENCE, AND CHARGED-PARTICLE ENERGIZATION IN THE TOPSIDE AURORAL IONOSPHERE AND MAGNETOSPHERE

In 1981, Chang and Coppi [Geophys. Res. Lett. 8, 1253 (1981)] suggested that lower-hybrid turbulence could be the prime candidate for the acceleration of ions and generation of ''ion conics'' in the high-latitude ionosphere and magnetosphere. Subsequently, Retterer, Chang, and Jasperse [J. Geophys. Res. 91, 1609 (1986)] demonstrated that nonlinear wave interactions near the lower-hybrid frequency through modulational instability, such as the collapse of waves into soliton (caviton) turbulence could play a key role in the energization of both the ambient ions and electrons. Recent sounding rocket observations in the source region of the topside auroral ionosphere seem to confirm the details of such predictions [Kintner et al., Phys. Rev. Lett. 68, 2448 (1992); Arnoldy et al., Geophys. Res. Lett. 19, 413 (1992)]. In this paper, the scenario of this interesting micro/meso scale, nonlinear wave-wave and wave-particle interaction plasma process in the auroral ionosphere/magnetosphere is briefly reviewed.