CoRoT-2b: a Tidally Inflated, Young Exoplanet?

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

CoRoT-2b is among the most anomalously large transiting exoplanet known. Due to its large mass (3.3 Mjup), its large radius ( 1.5 Rjup) cannot be explained by standard evolution models. Recipes that work for other anomalously large exoplanets (e.g. HD209458b), such as invoking kinetic energy transport in the planetary interior or increased opacities, clearly fail for CoRoT-2b. Interestingly, the planet's parent star is an active star with a large fraction (7 to 20%) of spots and a rapid rotation (4.5 days).
We first model the star's evolution to accurately constrain the planetary parameters. We find that the stellar activity has little influence on the star's evolution and inferred parameters. However, stellar evolution models point towards two kind of solutions for the star-planet system: (i) a very young system (20-40 Ma) with a star still undergoing pre-main sequence contraction, and a planet which could have a radius as low as 1.4 Rjup, or (ii) a young main-sequence star (40 to 500 Ma) with a planet that is slightly more inflated ( 1.5 Rjup). In either case, planetary evolution models require a significant added internal energy to explain the inferred planet size: from a minimum of 3x1028 erg/s in case (i), to up to 1.5x1029 erg/s in case (ii).
We find that evolution models consistently including planet/star tides are able to reproduce the inferred radius but only for a short period of time ( 10 Ma). This points towards a young age for the star/planet system and dissipation by tides due to either circularization or synchronization of the planet. Additional observations of the star (infrared excess due to disk?) and of the planet (precise Rossiter effect, IR secondary eclispe) would be highly valuable to understand the early evolution of star-exoplanet systems.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

CoRoT-2b: a Tidally Inflated, Young Exoplanet? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with CoRoT-2b: a Tidally Inflated, Young Exoplanet?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and CoRoT-2b: a Tidally Inflated, Young Exoplanet? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-839325

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.