DUST PARTICLE-EMISSION DYNAMICS FROM INSOLATED ICE DUST MIXTURES - RESULTS FROM THE KOSI-5 EXPERIMENT

In comet simulation (KOSI) experiments mineral-ice mixtures are studie d under space conditions. In this paper the temporal variation of emis sion events is studied during the irradiation phase in the experiment KOSI 5. Physical properties like mass, size and mean mass density of e mitted dust particles are investigated. Dynamical parametets of the pa rticle motion are determined from recorded trajectories close to the s ample surface. The drag coefficient governing the momentum transfer fr om the released gas to the emitted particle is also estimated. From th e trajectories, the spatial distribution of starting points of the res pective particles on the sample surface is estimated. These results su ggest a sample surface development in two phases: formation of dry dus t particles on the surface and, subsequently, further increase of the dust mantle.