300 likes | 390 Views
Dynamics of Extra-solar Planetary Systems with Hot Jupiters. USP-UNC team on Exoplanets:. C. Beaugé (UNC) S. Ferraz-Mello (USP) T. A. Michtchenko (USP). Why do we study the Dynamics of Extrasolar Planetary Systems ? To know how stable they are !.
E N D
Dynamics of Extra-solar Planetary Systems with Hot Jupiters USP-UNC team on Exoplanets: C. Beaugé (UNC) S. Ferraz-Mello (USP) T. A. Michtchenko (USP)
Why do we study the Dynamics of Extrasolar Planetary Systems ? To know how stable they are ! Ref: Brasil CoRoT week, Natal2004
3 (4) classes Ia – Planets in mean-motion resonances Ib – Low-eccentricity Non-resonant Planet Pairs II – Non-resonant Planets with a Significant Secular Dynamcis III – Weakly interacting Planet Pairs
GJ 876 (0,0) apsidal corotation resonance
SYMMETRIC APSIDAL COROTATIONS (0,0) Ref:Beaugé et al., Lee and Peale Hadjidemetriou et al. 2002-2003-2004
M0=1.15 Msun m1=1.7 Mjup/sin i m2=1.8 Mjup/sin i
The orbits of the least-squares solution are bound to a catastrophic event in less than 100,000 years. Ref: Ferraz-Mello et al. (ApJ 2005)
The planets of 47 UMa M = 2.9 M M = 1.1 M 1 Jup 2 Jup
Class Ib – Low-eccentricity Near-resonant pairs Outer Solar System
Solar System with Saturn initialized on a grid of different initial conditions 2/17/3 5/2 8/3 . 50 Myr Collision Chaos Order Grid: 33x251 Ref: Michtchenko (unpub.)
Class Ib – Low-eccentricity Near-resonant pairs Near Resonant Pulsar Planets
Neighborhood of the 3rd planet of pulsar B1257 +12 collision Grid: 21x101 Pulsar system initialized with planet C on a grid of different initial conditions. The actual position of planet C is shown by a cross. (N.B. I=90 degrees)
One question: (Brasil CoRoT week, Natal 2004) Is it possible to find a system of two close-in planets with period ratio close to 2.5?
Dynamical Map of the Neighborhood of the 5:2 MMR e1 e2=0.04 26x40 px cf TAM
TIDAL EVOLUTION OF SYSTEMS OF HOT JUPITERS DIVERGENT MIGRATION If the star rotation is slower than the orbital motion of the inner planet, the migration is divergent.
INTERACTION WITH RESONANCES Consequences: Enhancement of eccentricities and inclinations, semi-major axis discontinuities, but no capture into the resonance.
Example (highly hypothetical) Masses 0.82 Sun 1.1e-4 star 7.2e-4 star --2:1-- ----crossing Time units ~ 2 x 10 4to 5 x 10 5 years t41227.dat
(same example as before) 2:1 7:4 --- 3:1---- 5:2----
One more realistic example Masses 0.82 Sun 1.1e-4 star 7.2e-4 star Time units ~ 2 x 10 4to 5 x 10 5 years t41223.dat
(same example as before) 3:1 ------ t23e
SCALING: Adopted value of k2 / Q ~ 2 x 10-3 Actual values cf. Paetzold & Rauer, 2002 7 x 10-8 < k2 / Q < 2 x 10-6 Hence, the scaling is in the range 10 3to 3 x 10 4
Synchronization (due to tides raised on the planet) Scaling ~ 10 3 t41231.dat
The tidal theories fail to give the right period for large satellites (oceans ?) The spin-orbit synchronization weakens the action of torques due to planet tides. Only remaining effect: fast circularization
A new example. start: 2:1 ACR Tides on both star and planet Masses 0.82 Sun 8.2e-5 star 7.2e-4 star Time unit ~ 4 x 103 yrs t50323.dat
http://www.astro.iag.usp.br/~dinamica/usp-unc.htm @ArXiv: Astro-ph/0511xxx /0505169v2 /0404166 /0402335 /0301252 /0210577 Planet systems data (+ updates): See: http:// www.astro.iag.usp.br/~dinamica/exosys.htm
Data from: Ferraz-Mello et al (2005) [HD 82943], Laughlin et al (2005) [GJ 876], Vogt et al. (2005) [HD12831, HD 108871 and HD 37124], McArthur et al.(2004) [55 Cnc ], Correia et al. (2005) [HD 202206], Gozdziewski et al. (2005) [mu Ara = HD 160691], Santos et al. (2004) [HD 160691e], Mayor et al. (2004) [HD 169830], Fischer et al (2002) [HD 12661], Ford et al. (2005) [upsilon Andromedae], Konacki & Wolszczan (2003) [PSR 1257+12].