Wave-particle interactions in the complex environment of a comet
Wave-particle interactions have not been investigated thoroughly around comets, since very few comets have ever been visited. The cometary environment is very complex, comprising a mixture of plasma, neutrals, and dust (charged grains), and including complicated interactions with the solar wind. Dust introduces totally new phenomena, e.g. wave instabilities that do not occur in normal electron-ion plasmas. In the proposed project we will study wave-particle interactions in the environment of comet 67P/Churyumov- Gerasimenko. We will investigate how ions and dust (especially nanodust) can affect the waves, and how wave energy is redistributed among the particles. We will also study how the plasma and dust will be affected in the large scale environment of a comet, with implications for the solar wind interaction and cometary tail formation. We will use already available PIC (Particle-In-Cell) and hybrid codes developed by key members of our team to investigate the interaction in smaller and larger scale regions. Our results will be compared with data from the Rosetta mission, in particular from the Rosetta Plasma Consortium. The project addresses two major questions: * How are waves generated in the cometary environment, and how is wave energy re-distributed among the particles? * How does the large-scale cometary environment affect wave-particle interaction?