How fast do Jupiters grow? Signatures of the snowline and growth rate in the distribution of gas giant planets

• Published in: Monthly notices of the Royal Astronomical Society Vol. 428; no. 1; pp. 756 - 762
• Main Authors: Rice, Ken, Penny, Matthew T., Horne, Keith
• Format: Journal Article
• Language: English
• Published: London Oxford University Press 01.01.2013
• Subjects: Gases; Planets; Star & galaxy formation; planets and satellites: formation; planetary systems; stars: pre-main-sequence
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/sts079

We present here observational evidence that the snowline plays a significant role in the formation and evolution of gas giant planets. When considering the population of observed exoplanets, we find a boundary in mass-semimajor axis space that suggests that planets are preferentially found beyond the snowline prior to undergoing gap-opening inward migration and associated gas accretion. This is consistent with theoretical models suggesting that sudden changes in opacity - as would occur at the snowline - can influence core migration. Furthermore, population synthesis modelling suggests that this boundary implies that gas giant planets accrete ∼70 per cent of the inward flowing gas, allowing ∼30 per cent through to the inner disc. This is qualitatively consistent with observations of transition discs suggesting the presence of inner holes, despite there being ongoing gas accretion.