2016/09/20 by Caroline Terquem, Terquem, Caroline
Chemistry · Physics and Astronomy · #Astrophysics and Star Formation Studies #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Molecular Spectroscopy and Structure #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.1609.06056
openalex publication_date 2016/09/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In protoplanetary discs, planetary cores must be at least 0.1 earth mass at 1\nau for migration to be significant; this mass rises to 1 earth mass at 5 au.\nPlanet formation models indicate that these cores form on million year\ntimescales. We report here a study of the evolution of 0.1 earth mass and 1\nearth mass cores, migrating from about 2 and 5 au respectively, in million year\nold photoevaporating discs. In such a disc, a gap opens up at around 2 au after\na few million years. The inner region subsequently accrete onto the star on a\nsmaller timescale. We find that, typically, the smallest cores form systems of\nnon-resonant planets beyond 0.5 au with masses up to about 1.5 earth mass. In\nlow mass discs, the same cores may evolve in situ. More massive cores form\nsystems of a few earth masses planets. They migrate within the inner edge of\nthe disc gap only in the most massive discs. Delivery of material to the inner\nparts of the disc ceases with opening of the gap. Interestingly, when the heavy\ncores do not migrate significantly, the type of systems that are produced\nresembles our solar system. This study suggests that low mm flux transition\ndiscs may not form systems of planets on short orbits but may instead harbour\nearth mass planets in the habitable zone.\n