Protoplanetary Formation efficiency and time scale D.N.C. Lin University of California, Santa Cruz, KIAA, Peking University, China with K. Kretke, S. Watanabe, Shulin Li, I. Dobbs-Dixon, P.Garaud, Jilin Zhou, M. Nagasawa, H. Klahr, N. Turner, G. Ogilvie, H. Li, C. Agnor, ZX Shen, T. Takeuchi, G. Bryden, C. Beichman, E. Thommes Astronomy Department University of Florida Apr 14th, 2007 23 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 a frequency enhancement near the snow line? Is there an edge to the planetary systems? Does the mass function depend on the stellar mass or [Fe/H]? 2/23

Dependence on the stellar [Fe/H] Santos, Fischer & Valenti Frequency of Jovian-mass planets increases rapidly with [Fe/H]. But, the ESP’s 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]? 3/23

Disk evolution only external disk but accreting star Protostellar disks: Gas/dust = 100 Dabris disks: Gas/dust = 0.01 Transitional Disks (CG, Garaud) only external disk but accreting star 4/23

surface ripples and self shaddows 5/23 Watanabe, Kretke, Klahr

Retention of condensable grains Preferred site: snow line Gas-solid transition Local enrichment: abundances fractionation (Stevenson,Takeuchi) Kretke Kyoto minimum mass nebula model Cuzzi 6/23

The lively dead zone Horizontally-Averaged Magnetic Stress Versus Height and Time z Ideal MHD 100 Resistive MHD with Ionization Chemistry +4 -4 50 100 150 years time Lundquist number unity indicates marginal linear stability. Turner et al 07 7/23

Surface density distribution & ice grain retention Kretke 8/23

Disk-planet tidal interactions type-I migration type-II migration Lin & Papaloizou (1985),.... Goldreich & Tremaine (1979), Ward (1986, 1997), Tanaka et al. (2002) planet’s perturbation viscous diffusion disk torque imbalance viscous disk accretion 9/23

Competition: M growth & a decay 10 Myr 1 Myr 0.1 Myr Shen Limiting isolation Mass (Ida) Hyper-solar nebula x30 Metal enhancement does not always help! need to slow down migration 10/23

Embryos’ type I migration (10 Mearth) Cooler and invisic disks Warmer disks 11/23

Giant impacts Diversity in core mass Spin orientation Survival of satellites Retention of atmosphere Late bombardment of planetesimals (Zhou, Li, Agnor) 12/23 20/43

Flow into the Roche lobe H/a=0.07 Bondi radius (Rb=GMp /cs2) Hill’s 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* H/a=0.04 Dobbs-Dixon, Li 13/23

The period distribution: Type II migration 14/23 Disk depletion versus migration

Mean motion resonance capture Migration of gas giants can lead To the formation of hot earth Implication for COROT Zhou Tidal decay out of mean motion resonance (Novak & Lai) Impact enlargement Rejuvenation of gas Giant. HD 209458b (Guillot) 15/23 Detection probability of hot Earth Narayan, Cumming

Effect of type I & II migration Habitable planets M/s accuracy 16/23

Stellar mass-metallicity More data needed for high and low-mass stars 17/23

Dependence on M* 1) hJ increases with M* 2) Mp and ap increase with M* Do eccentricity and multiplicity depend on M*? 18/23

Migration-free sweeping secular resonances Resonant secular perturbation Mdisk ~Mp (Ward, Ida, Nagasawa) Transitional disks 19/23

Outer edge of planetary systems Bryden, Beichman 20/23

Migration, Collisions, & damping Late formation (10-50 Myr) Giant-embryo impacts Low eccentricities, stable orbits Nagasawa, Thommes Clearing of the asteroid belt Earlier formation of Mars Sun ward planetesimals 21/23

Sequential accretion scenario summary Damping & high S leads to rapid growth & large isolation masses at the snow line. Jupiter formed prior to the final assemblage of terrestrial planets within a few Myrs. 2) Emergence of the first gas giants after the disk mass was reduced to that of the minimum nebula model. 3) Planetary mobility promotes formation & destruction. Snow line is a good place to halt migration. 4) The first gas giants induce formation of other siblings. 5) Shakeup led to the dynamically porous configuration of the inner solar system & the formation of the Moon. 6) Earths are common and detectable within a few yrs! 22/23

Outstanding issues: Frequency of planets for different stellar masses Completeness of the mass-period distribution Signs of dynamical evolution Mass distribution of close-in planets: efficiency of migration Halting mechanisms for close-in planets Origin of planetary eccentricity Formation and dynamical interaction of multiple planetary systems Internal and atmospheric structure and dynamics of gas giants Satellite formation Low-mass terrestrial planets 23/23