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arXiv · 1603.08008

Making Planet Nine: Pebble Accretion at 250--750 AU in a Gravitationally Unstable Ring

Scott J. Kenyon·Benjamin C. Bromley
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Abstract

We investigate the formation of icy super-Earth mass planets within a gravitationally unstable ring of solids orbiting at 250-750 AU around a 1 solar mass star. Coagulation calculations demonstrate that a system of a few large oligarchs and a swarm of pebbles generates a super-Earth within 100-200 Myr at 250 AU and within 1-2 Gyr at 750 AU. Systems with more than ten oligarchs fail to yield super-Earths over the age of the solar system. As these systems evolve, destructive collisions produce detectable debris disks with luminosities of $10^{-5}$ to $10^{-3}$ relative to the central star.

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Scott J. Kenyon, Benjamin C. Bromley. 2016-03-25. Making Planet Nine: Pebble Accretion at 250--750 AU in a Gravitationally Unstable Ring. https://doi.org/10.3847/0004-637x/825/1/33

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