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arXiv · 1403.6552

The circulation of dust in protoplanetary discs and the initial conditions of planet formation

Bradley M. S. Hansen
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Abstract

We examine the consequences of a model for the circulation of solids in a protoplanetary nebula in which aerodynamic drag is counterbalanced by the recycling of material to the outer disc by a protostellar outflow or a disc wind. This population of circulating dust eventually becomes unstable to the formation of planetesimals by gravitational instability, and results in the ultimate deposition of 30--50 earth masses in planetesimals on scales R< 1 AU. Such a model may provide an appropriate justification for the approximately power law initial conditions needed to reproduce observed planetary systems by in situ assembly.

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Bradley M. S. Hansen. 2014-03-26. The circulation of dust in protoplanetary discs and the initial conditions of planet formation. https://doi.org/10.1093/mnras%2Fstu471

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