Starspots and spin-orbit alignment for Kepler cool host stars

  title={Starspots and spin-orbit alignment for Kepler cool host stars},
  author={Roberto Sanchis-Ojeda and Joshua N. Winn and Daniel C. Fabrycky},
  journal={Astronomische Nachrichten},
The angle between the spin axis of the host star and the orbit of its planets (i.e., the stellar obliquity) is precious info rmation about the formation and evolution of exoplanetary systems. Measurements of the Rossiter-McLaughlin effect revealed that many stars that host a hot-Jupiter have high obliquities, su ggesting that hot-Jupiter formation involves excitation o f orbital inclinations. In this contribution we show how the passage of the planet over starspots can be used to measure the… 

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