The photoevaporation of close-in exoplanets

Series: 
Astronomy Unit Seminars
Speaker: 
James Owen
Host: 
Sijme-Jan Paardekooper
Date: 
January 26th, 2018 at 14:30
Room: 
GO Jones Room 610
Abstract: 

The abundance of close-in super-earth/sub-neptunes is one of the big surprises from the Kepler mission. Most stars appear to host one of these planets yet they were completely missing from our ideas of how planet formed a decade ago. The fact that many of these planets have large volatile H/He atmospheres at small separations indicates that hydrodynamic escape of these atmospheres cannot be ignored. Combining recent observational advances from the California-Kepler Survey, with a theoretical understanding of how exoplanetary atmospheres evolve I will provide clues as to how close-in, small planets formed. This will include inferences gleaned from the "evaporation-valley" and how the properties of these planets vary with host star metallicity.