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Title:
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Authors:
Jürgen Blum, Technical University at Braunschweig
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Abstract:
Over the past decade, considerable progress has been achieved in our understanding of the conditions under which dust grows (i.e. coagulates or agglomerates) in protoplanetary disks. Laboratory and space experiments have resulted in quite a number of parameters that determine the outcome of a collision between pre-planetesimal bodies, ranging from very low-velocity collisions of individual micrometer dust particles and small, fractal dust agglomerates to higher-speed impacts into decimeter-sized porous dust aggregates. This has led to a well-understood description of the growth rate and morphology of pre-planetary dust agglomerates in the micrometer to decimeter size range. However, the probably most crucial step in preplanetary evolution, the growth from decimeter- to 10-meter-sized bodies, is still not well understood. Experiments to test the different hypotheses for this growth stage are under way and will also be reviewed.
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