Contributed Talk - Splinter Exoplanets

Thursday, 24 September 2020, 10:00   (virtual room D)

a compositional link between
 warm super-Earths and cold Jupiters

M. Schlecker, C. Mordasini, A. Emsenhuber, H. Klahr, Th. Henning, R. Burn, Y. Alibert, W. Benz
Max-Planck-Institut für Astronomie, Heidelberg; University of Bern; University of Arizona

Recent demographic studies have suggested a positive correlation between the occurrence rates of inner super-Earths and outer giant planets, challenging some established planet formation theories. We set out to test this correlation by simulating a large number of multi-planet systems in a core accretion context, which we compared to the observed exoplanet systems. A peculiar trend emerges when we associate the disk properties of our model with the bulk composition of inner low-mass planets: in disks of moderate solid content (~100 Mearth), super-Earths form from icy material beyond the water ice line and migrate to observable distances. No giant planets are formed. On the other hand, in massive disks (~>200 Mearth), dry super-Earths form on close orbits and are frequently accompanied by an outer gas giant. This results in the testable hypothesis that high-density inner super-Earths are proxies for cold Jupiters in the same system. I will discuss how observational confirmation of this prediction has the power to constrain central open questions in contemporary planet formation theory, ranging from efficiency of pebble accretion to planet migration.