J/ApJ/692/L9 Tidal evolution of transiting extrasolar planets (Levrard+, 2009)
Falling transiting extrasolar giant planets.
Levrard B., Winisdoerffer C., Chabrier G.
<Astrophys. J., 692, L9-L13 (2009)>
=2009ApJ...692L...9L 2009ApJ...692L...9L
ADC_Keywords: Planets ; Models, evolutionary ; Stars, masses ;
Rotational velocities ; Stars, double and multiple
Keywords: celestial mechanics - planetary systems: formation - planetary
systems: protoplanetary disks
Abstract:
We revisit the tidal stability of extrasolar systems harboring a
transiting planet and demonstrate that, independently of any tidal
model, none, but one (HAT-P-2b) of these planets has a tidal
equilibrium state, which implies ultimately a collision of these
objects with their host star. Consequently, conventional
circularization and synchronization timescales cannot be defined
because the corresponding states do not represent the endpoint of the
tidal evolution. Using numerical simulations of the coupled tidal
equations for the spin and orbital parameters of each transiting
planetary system, we confirm these predictions and show that the
orbital eccentricity and the stellar obliquity do not follow the
usually assumed exponential relaxation but instead decrease
significantly, eventually reaching a zero value only during the final
runaway merging of the planet with the star. The only characteristic
evolution timescale of all rotational and orbital parameters is the
lifetime of the system, which crucially depends on the magnitude of
tidal dissipation within the star. These results imply that the nearly
circular orbits of transiting planets and the alignment between the
stellar spin axis and the planetary orbit are unlikely to be due to
tidal dissipation. Other dissipative mechanisms, for instance
interactions with the protoplanetary disk, must be invoked to explain
these properties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 152 25 Values and uncertainties of parameters relevant
to tidal evolution of transiting planetary systems
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See also:
J/A+A/510/A107 : TrES-2b multi-band transit observations (Mislis+, 2010)
J/MNRAS/408/1494 : Planetary transits of TrES-2 and TrES-3 (Colon+, 2010)
J/MNRAS/408/1680 : Transiting planetary system WASP-2 (Southworth+, 2010)
J/A+A/500/L45 : Observations of transits of the TrES-2 exoplanet (Mislis+,
2009)
J/A+A/508/1011 : Planetary transit of TrES-1 and TrES-2 (Rabus+, 2009)
J/A+A/503/601 : HD 17156 transit photometry + radial velocities (Barbieri+,
2009)
J/AJ/136/267 : Six occultations of the exoplanet TrES-3 (Winn+, 2008)
J/ApJ/675/1531 : Transits of super-Neptune HD 149026b (Winn+, 2008)
J/A+A/475/1125 : Characterization of the hot Neptune GJ 436b (Demory+, 2007)
J/ApJ/657/1098 : Transit of TrES-1 (Winn+, 2007)
J/ApJ/664/1185 : Three transits of the exoplanet TrES-2 (Holman+, 2007)
J/AJ/133/1828 : Transit light curves of HD 189733 (Winn+, 2007)
J/ApJ/655/1103 : Five transits of the exoplanet OGLE-TR-10b (Holman+, 2007)
J/A+A/466/743 : Transiting planet OGLE-TR-132b (Gillon+, 2007)
J/ApJ/649/1043 : Transiting extrasolar planet HD 209458b (Richardson+, 2006)
J/A+A/424/L31 : Transiting exoplanet OGLE-TR-132b (Moutou+, 2004)
J/ApJ/582/1123 : Search for transiting extrasolar planets (Mallen-Ornelas+,
2003)
J/A+A/392/215 : The CORALIE survey for extrasolar planets. IX. (Santos+,
2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Planetary system name
13- 17 F5.3 Mjup Mp Planetary mass in Jupiter masses
19- 23 F5.3 Mjup e_Mp Uncertainty in Mp
25- 27 A3 --- r_Mp Source(s) of Mp and e_Mp (1)
29- 33 F5.3 --- Rp Planetary radius in Jupiter radii
35- 39 F5.3 --- RpMin Lower limit value in Rp
41- 45 F5.3 --- RpMax Upper limit value in Rp
47- 49 A3 --- r_Rp Source(s) of Rp and Limit value in Rp (1)
51- 61 F11.8 d Torb Orbital period
63- 65 A3 --- r_Torb Source(s) of Torb (1)
67- 73 F7.5 AU a Separation
75- 82 F8.6 AU e_a Uncertainty in a
84- 88 A5 --- r_a Source(s) of a and e_a (1)
90- 94 F5.3 Msun Mstar Stellar mass
96-100 F5.3 Msun e_Mstar Uncertainty in Mstar
102-104 A3 --- r_Mstar Source(s) of Mstar and e_Mstar (1)
106-110 F5.3 Rsun Rstar Stellar radius
112-116 F5.3 Rsun e_Rstar Uncertainty in Rstar
118-122 A5 --- r_Rstar Source(s) of Rstar and e_Rstar (1)
124 A1 --- l_vsini Limit flag on vsini
125-129 F5.2 km/s vsini Projected stellar rotation velocity (2)
131-134 F4.2 km/s e_vsini ? Uncertainty in vsini
136-138 A3 --- r_vsini Source(s) of vsini and e_vsini (1)
140-144 F5.3 --- e ? Orbital eccentricity
146-150 F5.3 --- e_e ? Uncertainty in e
152 A1 --- r_e Source of e and e_e (1)
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Note (1): References as follows:
a = http://exoplanet.eu/catalog-transit.php;
b = http://www.inscience.ch/transits/;
c = Fischer et al. (2007ApJ...669.1336F 2007ApJ...669.1336F);
d = Barbieri et al. (2007A&A...476L..13B 2007A&A...476L..13B);
e = Loeillet et al. (2008A&A...481..529L 2008A&A...481..529L);
f = Sato et al. (2005ApJ...633..465S 2005ApJ...633..465S);
g = Winn et al. (2008, Cat. J/ApJ/675/1531);
h = Gaudi & Winn (2007ApJ...655..550G 2007ApJ...655..550G);
i = Pont et al. (2007A&A...465.1069P 2007A&A...465.1069P);
j = Laughlin et al. (2005ApJ...629L.121L 2005ApJ...629L.121L);
k = Demory et al. (2007, Cat. J/A+A/475/1125);
l = Alonso et al. (2004ApJ...613L.153A 2004ApJ...613L.153A);
m = O'Donovan et al. (2006ApJ...651L..61O 2006ApJ...651L..61O);
n = Laughlin et al. (2005ApJ...621.1072L 2005ApJ...621.1072L);
p = O'Donovan et al. (2007ApJ...663L..37O 2007ApJ...663L..37O);
q = Mandushev et al. (2007ApJ...667L.195M 2007ApJ...667L.195M);
r = McCullough et al. (2006ApJ...648.1228M 2006ApJ...648.1228M);
s = Bakos et al. (2007ApJ...656..552B 2007ApJ...656..552B);
t = Torres et al. (2007ApJ...666L.121T 2007ApJ...666L.121T);
u = Kovacs et al. (2007ApJ...670L..41K 2007ApJ...670L..41K);
v = Bakos et al. (2007ApJ...671L.173B 2007ApJ...671L.173B);
w = Noyes et al. (2008ApJ...673L..79N 2008ApJ...673L..79N);
x = Stempels et al. (2007MNRAS.379..773S 2007MNRAS.379..773S);
y = Cameron et al. (2007MNRAS.375..951C 2007MNRAS.375..951C);
z = Pollacco et al. (2008MNRAS.385.1576P 2008MNRAS.385.1576P);
A = Melo et al. (2006A&A...460..251M 2006A&A...460..251M);
B = Konacki et al. (2005ApJ...624..372K 2005ApJ...624..372K);
C = Pont et al. (2004A&A...426L..15P 2004A&A...426L..15P);
D = Bouchy et al. (2004A&A...421L..13B 2004A&A...421L..13B);
E = Pont, F., pers. comm.
* = estimated via Kepler's law;
** = based on the average of Loeillet et al. (2008A&A...481..529L 2008A&A...481..529L), Bakos et
al. (2007ApJ...670..826B 2007ApJ...670..826B) and Winn et al. (2007ApJ...665L.167W 2007ApJ...665L.167W);
*** = estimated via chromospheric activity (≃45 days by Demory et al.
2007, Cat. J/A+A/475/1125).
Note (2): The stellar rotation velocity is determined from available data
on star chromospheric activity and/or from the value of the projected
velocity vsin(i)star, obtained from Doppler spectroscopic
measurements, where istar is the angle between the stellar rotation
axis and the line-of-sight, that we assumed to be close to 90°.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-Feb-2011