Seminar by Emil Knudstrup on migration histories of exoplanets

Seminar by Emil Knudstrup from Chalmers.

Title: Transporting Giant Planets: A Logistical Nightmare.

Abstract: From the get-go the exoplanet field has been packed with surprising system architectures; hot Jupiters, planets on extremely eccentric orbits, planets in binary systems, planets around binary systems. Just to name a few curiosities, completely different from the Solar System. This diversity for the exoplanet system architectures also extends to the stellar obliquities, where we have discovered planets on prograde, polar, and even retrograde orbits. These measurements of the (sky-projected) obliquity, mostly obtained through the Rossiter-McLaughlin effect, have given rise to some interesting questions.  Is there really a Preponderance of Perpendicular Planets, or does it perhaps only pertain to particular populations of planets? If hot Jupiters form through high-eccentricity migration, it is tantalizing to think there should be a connection between the obliquity and eccentricity, but do we see that? And what role do tides play in shaping the architectures?  In this talk, we will discuss these questions as well as the key observables involved and some of the challenges we face when trying to infer the migration history from these.