The migration of giant planets in massive protoplanetary discs

Abstract

If giant planets form by disc fragmentation early on during disc evolution, then they interact with the gas in the disc and as a result they will likely migrate, i.e. drift inwards or outwards. This study aims to explore the migration patterns of giant planets in unstable discs using radiative hydrodynamic simulations. More specifically we examine the migration of planets within different mass discs and at different orbital radii. We find that planets initially migrate inwards quickly. They are able to open up a gap and the migration stops and turns to a slow outward migration. Therefore, planets forming early on are able to survive on wide orbits. However, many of these planets accrete enough mass to become brown dwarfs. This could explain the observations of giant planets at wide orbital radii from the host star.