Dust dynamics in forming resonant planetary systems

A fraction of the known planetary systems are observed in (or close to) mean motion resonances. These sample provides a unique opportunity, since they preserve the condition of their formation and early evolution of their orbits. The dynamics of the gas and dust in these systems is particularly interesting, as the resonant planets can open a common gap and migrate together. If the migration is directed outwards, the dusty ring formed at the outer edge of the gap would move together with the planets, potentially disentagling the dust distribution from the gas one. During planet migration the dust overdensity encounters several ice lines that suddenly change the dust size distribution, and thus its dynamical coupling with the gas and the gravitational interaction with the planets, potentially affecting its concentration. We modelled the evolution of a sample of protoplanets embedded in their natal disk with the hydrodynamical code PLUTO where a population of Lagrangian particles is introduced to track the dynamical evolution of a range of particles from dust to planetesimals. We focus in particular on the effect that dust evaporation/condensation at the ice-lines might have on the dust concentration at the gap edge during planet migration. We generate mock observations and discuss the role of ice lines on the observability of transition and debris disks.