The effect of tidal inflation instability on the mass and dynamical evolution of extrasolar planets with ultrashort periods

摘要: We investigate the possibility of substantial inflation short-period Jupiter-mass planets, as a result their internal tidal dissipation associated with synchronization and circularization orbits. employ simplest prescription based on an equilibrium model constant lag angle for all components tide. show following: (1) In low-eccentricity limit, planets' spin mean motion is established before can significantly modify structure. (2) However, above critical eccentricity, which function semimajor axis, energy during process induce planets to inflate in size eccentricity damped. (3) For moderate eccentricities, adjust stable thermal equilibria rate balanced by enhanced radiative flux enlarged radii. (4) sufficiently large swell beyond two Jupiter radii degeneracy partially lifted. Thereafter, become unstable they undergo runaway until exceed Roche radius. (5) determine necessary sufficient condition this instability. (6) These results are applied study planets. that young period less than 3 days, initial radius about 2RJ, orbital greater 0.2, dissipated orbits intense protracted sizes up (7) estimate mass-loss rate, asymptotic planetary masses, axes various parameters. The gas overflow through both inner (L1) outer (L2) Lagrangian points short periods or eccentricities discussed. (8) Planets more modest ( 0.03-0.04 AU) lose mass via lobe mostly point. As conservation total angular momentum, these mass-losing migrate outward, such increase while mass, decrease loss quenched. (9) Based results, we suggest combined effects self-regulated tidally driven evolution may be responsible apparent lack giant ultrashort days. (10) Mass also have caused range ~3-7 days massive long-period not affected star-planet interaction. (11) accretion debris lead surface layer contamination metallicity enhancement host stars. (12) Among 1-3 weeks today, some migrated outward attained circular others preserved axis. Therefore, expected coexist those eccentric range. (13) Gross occurs timescale ~106 yr after formation brief interval ~105 yr. relatively classical weak-line T Tauri stars transit probability. inflated heated eclipse depth events. Thus, disruption directly observable around