Astronomy and Astrophysics – Astronomy
Scientific paper
Jul 2007
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007dda....38.1502j&link_type=abstract
American Astronomical Society, DDA meeting #38, #15.02
Astronomy and Astrophysics
Astronomy
Scientific paper
Eccentricities e of extrasolar planets with semimajor axes a > 0.1 AU are large, averaging 0.24 and broadly distributed up to near 1. For smaller a, eccentricities are much smaller (most < 0.2), which is widely attributed to damping by tides after the planets formed and the gaseous disk dissipated. Previous estimates of the damping rates considered the tide raised on the planet by the star, but ignored the tide raised on the star. Also, specific values were assumed for the planet's poorly constrained tidal dissipation parameter Q. Perhaps most important, the strongly coupled evolution between a and e was ignored. We have now integrated the full coupled tidal evolution equations for e and a over the estimated age of each planet, and confirm that the distribution of initial e values of close-in planets can match that of the general population. Eccentricity distributions are best matched for stellar and planetary Q values of 1e5 and 1e6, respectively. The accompanying coupled tidal evolution of the a values (mutually dependent on the evolution of e) was also significant: At the start of tidal migration, all planets had a > 0.06 AU, significantly larger than current values. It appears that gas disk migration did not bring planets closer than 0.06 AU, and that the current smaller values of a were only reached gradually due to tides over the lifetimes of the planets. Models of the early physical evolution of "hot Jupiters” should take into account that those planets were significantly farther from the stars when the gas disk dissipated than they are now.
Barnes Robin
Greenberg Richard
Jackson Brian
No associations
LandOfFree
Tidal Evolution of Extrasolar Planets 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 Tidal Evolution of Extrasolar Planets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tidal Evolution of Extrasolar Planets will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1662684