Origin of the inclination-width difference between inner-planet subsamples

Determine whether the apparent difference in the minimum mutual-inclination distributions of systems hosting giant versus lower-mass inner transiting planets reflects differences in formation history or subsequent dynamical evolution.

Background

The paper finds that systems hosting giant inner transiting planets have a posterior-inferred Rayleigh width of approximately 6.7 degrees, whereas systems hosting lower-mass inner planets have a broader width of approximately 18.1 degrees. Although the posterior probability that the giant-inner-planet subsample has a smaller inclination width is 0.952, a model with independent Rayleigh widths is not significantly favored over a shared-width model.

Consequently, the apparent mass-dependent trend is treated as suggestive rather than conclusive. The unresolved issue is whether any genuine difference arises from distinct planetary formation pathways or from subsequent dynamical evolution, such as inclination excitation by distant giant companions.