Statistics of Long Period Gas Giant Planets in Super-Earth Systems

The presence of a substantial population of volatile-rich super-Earths on orbits interior to 1 AU poses a challenge to models of planet formation and migration.  There is currently an ongoing debate as to whether these planets could have formed in situ or instead migrated inward from a more distant formation location.  We use radial velocity observations to search for massive, long-period gas giant companions in 65 super-Earth systems in order to constrain possible formation and migration scenarios. We find that the occurrence rate of Jupiter analogs in super-Earth systems is significantly higher than the occurrence rate of gas giant planets around field stars.  We conclude that, contrary to some theoretical predictions, the presence of outer gas giant planets does not suppress the formation of inner super-Earths.  We consider possible explanations for the observed correlation, including higher-than-average primordial disk masses and potential dynamical effects of these companions.

Submitted by