This project will use a two-dimensional electromagnetic Darwin particle-in-cell simulation determine self-consistently how whistler waves are generated in the magnetosphere for a variety of conditions and to understand the ensuing wave-particle interactions. Non-linear wave-particle and wave-wave interactions are important aspects of this problem necessitating the use of particle in cell simulations. Recent observational and theoretical work has shown that whistler-mode waves can propagate obliquely with respect to the ambient magnetic field, so a multidimensional approach is required. The simulations will be run on a next-generation computational platform that will allow the inclusion of realistic parameters for the radiation belt region and will be used in close coordination with observed wave and particle data to study the growth, amplitudes, and wave propagation characteristics of whistler waves and for chorus waves, the formation of their structured spectra, and the general effects whistlers have on electrons in terms of energization and pitch angle scattering.
Whistler waves, which are ubiquitous in the radiation belt region, play a major role in the transport, acceleration and loss of electrons. Whistlers are observed with a variety of characteristics and are sometimes smooth and unstructured, but other times are observed as bursty and structured. The structured and bursty types of emissions are commonly referred to as chorus. Understanding the role waves play in the formation of relativistic electron populations in the radiation belt region is key to space weather studies because of the deleterious effects these electrons can have on satellites. The research program here uses a first principles, self-consistent simulation approach to understand the fundamental problem concerning the origin of VLF whistler waves and the energization of inner-magnetospheric plasmas.
