1 / 18

Tidal interactions of close-in extrasolar planets with their host stars Ludmila Carone

Tidal interactions of close-in extrasolar planets with their host stars Ludmila Carone Institut für Geophysik und Meterologie Universität zu Köln, Cologne, Germany 5th Corot Week, 11. December 2003 in Berlin. Very close-in extrasolar planets. Tides raised by the star on the planet.

neila
Télécharger la présentation

Tidal interactions of close-in extrasolar planets with their host stars Ludmila Carone

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tidal interactions of close-in extrasolar planets with their host stars Ludmila Carone Institut für Geophysik und Meterologie Universität zu Köln, Cologne, Germany 5th Corot Week, 11. December 2003 in Berlin

  2. Very close-in extrasolar planets

  3. Tides raised by the star on the planet • Close-in extrasolar planets (a < 0.05 AU) experience extreme gravitational interaction • ->Tidal bulge on planet -> synchronous rotation (rotation = revolution)

  4. Time to reach synchronous rotation • Tides raised by the star on the planet • -> synchronous rotation of the planet -> depends on planetary mass and radius

  5. Time to reach synchronous rotation all planets a < 0.20 AU

  6. Tides raised by the planet on the star • Tidal bulge on the host star • -> increase/decrease of semi major axis -> decrease/increase of stellar rotation

  7. Tidal evolution • Tides raised by the planet on the star • decrease/increase of semi major axis • Spin-up/decrease of star rotation depends on planetary mass and star radius

  8. The parameters k* and Q* • Evolution time scale depends strongly on stellar love number k*and the stellar tidal dissipation factor Q* • Pätzold & Rauer (2002) favor:

  9. OGLE-TR-56b (an extreme planet) • OGLE-TR-56b was discovered during the OGLE-survey (Konacki et al, 2003) • Parameters: • extremly close distance to its host star & large mass -> very strong tidal interactions

  10. OGLE-TR-56b: Evolution of semi major axis

  11. OGLE-TR-56b: Evolution of stellar rotation

  12. OGLE-TR-56b: Evolution of stellar rotation(only in convection envelope)

  13. Time to reach roche limit

  14. Conclusion • OGLE-TR-56b may reach the roche limit within the lifetime of its host star • Tidal effects could lead to a considerable spin up in stellar rotation • Even more so, when only spin-up in convection envelope is considered (no friction between core and envelope) • The strength of tidal effects depends strongly on the planet‘s mass and the semi major axis • But for a better prediction the geophyisical properties Q* and k* have to be determined -> we need more data

  15. Very close-in extrasolar planets

  16. OGLE-TR-3b: Evolution of semi major axis

  17. OGLE-TR-3b: Evolution of stellar rotation

  18. OGLE-TR-3b: Evolution of stellar rotation(only in convection envelope)

More Related