Generation of EMIC rising-tone emissions and associated precipitations of energetic protons and relativistic electrons in the inner magnetosphere (Invited)

Abstract:

Coherent electromagnetic ion cyclotron (EMIC) emissions with rising frequencies are generated by energetic protons in the equatorial region of the Earth's inner magnetosphere as observed by spacecraft such as Akebono, Cluster, and THEMIS [1,2,3,4]. Hybrid code simulations successfully reproduce EMIC emissions and show that a substantial amount of protons is scattered into the loss cone through the nonlinear growth of EMIC waves with rising frequencies [5]. The emissions can also interact with relativistic electrons, inducing effective pitch angle scattering of them through nonlinear wave trapping [6]. Recent progress of observations, theory, and simulations of the nonlinear wave-particle interactions will be reviewed.

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