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Detection and Characterization of Jovian Planets D.N.C. Lin University of California, Santa Cruz with Exo Planet Task Force National Science Foundation Feb 20th, 2007 S. Ida, H. Li, S.L. Li, I. Dobbs-Dixon, J.L. Zhou, M. Nagasawa, P. Garaud, E. Thommes, R. Lange, G. Ogilvie, S.J. Aarseth, M. Evonuk Doug Lin: 48 slides Mass-period distribution A continuous logarithmic period distribution A pile-up near 3 days and another pile up near 2-3 years Does the mass function depend on the period? Is there an edge to the planetary systems? Does the mass function depend on the stellar mass or Fe/H? 2/48 Dependence on the stellar Fe/H Santos, Fischer & Valenti Frequency of Jovian-mass planets increases rapidly with Fe/H. But, the ESPs mass and period distribution are insensitive to Fe/H! Is there a correlation between Fe/H & hot Jupiters ? Do multiple systems tend to associated with stars with high Fe/H? 3/48 Dependence on M* 1) hJ increases with M* 2) Mp and ap increase with M* Do eccentricity and multiplicity depend on M*? 4/48 Multiple systems Diversity in mass distribution Resonant system with limited mass What fraction of Jovian mass planets reside in multiple systems? Is multiplicity more correlated with Fe/H or M* than single planets? 5/48 Planetary interior: diverse structure & Fe/H HD149026b: 67 earth-mass core 6/48 Avenues of planet formation 7/48 Disk evolution 8/48 Protostellar disks: Gas/dust = 100 Dabris disks: Gas/dust = 0.01 only external disk but accreting star Transitional disks Hillenbrand & Meyer 2000 Inner disks disappear 10 Myr a Per PleiadesHyades Ursa Major TW Hyd N2264 IC 348 L1641b Lupus Cha ONC N7128 LHa101 Taurus L1641y Mon R2 N1333 CrA Trap N2024 r Oph 0.11101001 Gyr Age (Myr) 0.0 0.2 0.4 0.6 0.8 1.0 Fraction of disks 9/48Gas accretion rate Potential observational signatures Coexistence of gas and solid phase volatile ices Evolution of snow line 10/48 Condensation sequence Meteorites: Dry, chondrules & CAIs Icy moons 11/48 Signs of Crystalline grains Bouwman Apai 12/48 13/48 Chondritic meteorites 1) Limited size range, sm-cm, 2) Glass texture, flash heating, 3) Age difference with CAIs, 4) Matrix glue & abundance, 5) Weak tensile strength. 6) Formation timescale 2-3 Myr 14/48 From dust to planetesimals Retention of heavy elements: tgrowthSdust but tdecay Sgas 15/48 Feeding zones: D 10 rHill Isolation mass: Misolation S1.5 a3 From planetesimals to embryos Initial growth: (runaway) 16/48 Growth during gas depletion Rapid damping: many small residual embryos. Slow damping: large eccentricity Delicate balance: Kominami & Ida Separation of eccentricity Excitation and damping is Needed! 17/48 type-II migration planets perturbation viscous diffusion type-I migration disk torque imbalance Disk-planet tidal interactions viscous disk accretion Goldreich & Tremaine (1979), Ward (1986, 1997), Tanaka et al. (2002) Lin & Papaloizou (1985), 18/48 Competition: M growth & a decay Hyper-solar nebula x30 Metal enhancement does not always help! need to slow down migration 10 Myr 1 Myr 0.1 Myr Limiting isolation mass 19/48 Embryos type I migration (10 Mearth) Cooler and invisic disks Warmer disks 20/48 (Mass) growth vs (orbital) decay Loss due to Type I migration Jovian-mass ESPs are rare around late-type stars Embryos migration time scale Outer embryos are better preserved only after significant gas depletion Critical-mass core:Mp=5Mearth 21/48 Preferred cradles of gas giants: snow line Limited by: Isolation slow growth 22/48 Accretion onto cores Challenges: 1) Core growth: perturbation slow down & planetesimal gaps (Ida) 2) Radiation transfer efficiency grain survival & opacity (Podolak) 2) 3) Low global Sdust (Bryden) Pollack et al Bodenheimer Korycansky 23/48 Giant impacts 1) Diversity in core mass 2) Spin orientation 3) Survival of satellites 4) Retention of atmosphere 24/48 Late bombardment of planetesimals Flow into the Roche lobe Bondi radius (Rb=GMp /cs2) Hills radius (Rh=(Mp/3M* )1/3 a) Disk thickness (H=csa/Vk) Rb/ Rh =31/3(Mp /M*)2/3(a/H)2 decreases with M*25/48 H/a=0.07 H/a=0.04 Effect of type I migration 26/48 Habitable planets M/s accuracy The period distribution: Type II migration Disk depletion versus migration 27/48 short-period cutoff Stopping mechanisms: 1) magnetospheric cavity 2) stellar tidal barrier 3) protoplanetary consumption 4) planetary tidal disruption Prediction: 90% disruption of hot Jupiters Bimodal Q*: prevalence of 1-day planets Ogilvie Tidal inflation Bodenheimer 28/48 Stellar metallicity, mass loss, & circularization of hot Jupiters 1)Early formation 2)Extensive migration 3)High mortality rate 4)Planetary mass loss 5)Tidal circularization 6)Signs of evolution? Transits: atmosphere & structure 29/48 period cutoffs depletion vs growth time Ice giants: Collisions vs ejections Prediction: period fall-off Test: gravitational lense 30/48 The mass distribution Origin of desert: Runaway gas accretion Bryden 31/48 Metallicity dependence Fe/H Two determining factors for the slope: 1) Heavy element retention efficiency, growth vs accretion 2) Growth rate and isolation mass of embryos 32/48 Stellar mass-metallicity 33/48 More data needed for high and low-mass stars Multiple planets a) Induced formation of multiple giants b) Resonant planets c) Formation time scale comparable to migration Bryden 34/48 Migration-free sweeping secular resonances Resonant secular perturbation Mdisk Mp (Ward, Ida, Nagasawa) Ups And Transitional disks 35/48 Dynamical shake up (Nagasawa, Thommes) Bodes law: dynamically porous terrestrial planets orbits with low eccentricities with wide separation 36/48 Migration, Collisions, & damping 1. Clearing of the asteroid belt 2. Earlier formation of Mars 3. Sun ward planetesimals A. Late formation (10-50 Myr) B. Giant-embryo impacts C. Low eccentricities, stable orbits 37/48 Giant impact & lunar formation 1) Lunar material similar to the Earths crust. 2) Formation after the differentiation (30 Myr) 3) Mars-size impactor 4) Post impact circular orbit Formation after 60 Myr Formation on 30-60 Myr 38/48 Sweeping clear of planetesimals Sweeping secular resonance & gas drag b Pic:Duncan, Nagasawa 39/48 Last melting events of chondrules Flash heating: Large S : evaporation Medium S : melting Small S : preservation 40/48 Sweeping secular resonance in ESPs Excitation of e & tidal inflation in HD209458 & disruption in 55 Can Gu, Ogilvie, Bodenheimer, Laughlin Rotational flattening & precession Nagasawa, Mardling Triple system around Ups And 41/48 Formation of warm Neptunes Jupiter-Saturn secular interaction & multiple extrasolar systems Relativistic detuning in m Arae 42/48 Post Depletion Dynamical Stability Dynamical filling factor: e excitation & chaos 43/48 Rayleigh distribution Mean motion resonance capture Tidal decay out of mean motion resonance (Novak & Lai) Impact enlargement Rejuvenation of gas Giant. HD 209458b (Guillot) Detection probability of hot Earth Narayan, Cumming Migration of gas giants can lead To the formation of hot earth Implication for COROT Zhou 44/48 A 2 Mearth “hot rock” planet in a 7-d orbit observed for 6 months with APF 1.3 m/s precision Easily detected!Easily detected! But this short-period planet But this short-period planet is is muchmuch too hot for habitability too hot for habitability 45/48 Frequency of Earth 46/48 1 Mearth planet in a 35-d habitable-zone orbit around a nearby M dwarf observed for 6 months with a 9- telescope global array 2.0 m/s precision Easy detection!Easy detection! 47/48 Sequential accretion scenario summary 1) Damping & high S leads to rapid growth & large isolation masses. Jupiter formed prior to the final assemblage of terrestrial planets within a few Myrs. 2) Emergence of the f