http://arxiv.org/abs/1801.06094
The satellites of Jupiter are thought to form in a circumplanetary disc. Here we address their formation and orbital evolution with a population synthesis approach, by varying the dust-to-gas ratio, the disc dispersal timescale and the dust refilling timescale. The circumplanetary disc initial conditions (density and temperature) are directly drawn from the results of 3D radiative hydrodynamical simulations. The disc evolution is taken into account within the population synthesis. The satellitesimals were assumed to grow via streaming instability. We find that the moons form fast, often within $10^4$ years, due to the short orbital timescales in the circumplanetary disc. They form in sequence, and many are lost into the planet due to fast type I migration, polluting Jupiter’s envelope with typically $0.3$ Earth-masses of metals, and up to $10$ Earth-masses in some cases. The last generation of moons can form very late in the evolution of the giant planet, when the disc has already lost more than the $99\%$ of its mass. The late circumplanetary disc is cold enough to sustain water ice, hence not surprisingly the $85\%$ of the moon population has icy composition. The distribution of the satellite-masses is peaking slightly above Galilean masses, up until a few Earth-masses, in a regime which is observable with the current instrumentation around Jupiter-analog exoplanets orbiting $1$ AU away from their host stars. We also find that systems with Galilean-like masses occur in $20\%$ of the cases and they are more likely when discs have long dispersion timescales and high dust-to-gas ratios.
M. Cilibrasi, J. Szulagyi, L. Mayer, et. al.
Fri, 19 Jan 18
6/68
Comments: 14 pages, 17 figures. Submitted to MNRAS, comments are welcome