1. 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

2. 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

3. 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

4. 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

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

6. 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

7. 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

8. Surface density distribution & ice grain retention
Kretke
8/23

9. 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

10. 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

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

12. 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

13. 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

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

15. 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 b
(Guillot)
15/23
Detection probability of hot Earth Narayan, Cumming

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

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

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

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

20. Outer edge of planetary systems
Bryden, Beichman
20/23

21. 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

22. 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

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