11
Lyot Lyot ConferenceConference
5 June 20075 June 2007
Properties of Properties of ExoplanetsExoplanets::from Giants toward Rocky Planetsfrom Giants toward Rocky Planets
& & InformingInforming Coronagraphy Coronagraphy
Collaborators:Collaborators: Paul Butler, Debra Fischer, Steve VogtPaul Butler, Debra Fischer, Steve Vogt
Chris McCarthy, Jason Wright, John Johnson, Katie PeekChris McCarthy, Jason Wright, John Johnson, Katie PeekChris Chris TinneyTinney, Hugh Jones, Brad Carter, Hugh Jones, Brad Carter
Greg Laughlin, Doug Lin, Shigeru Ida, Jack Greg Laughlin, Doug Lin, Shigeru Ida, Jack LissauerLissauer, , Eugenio Eugenio RiveraRivera
--Stellar Sample -Stellar Sample -
1330 Nearby FGKM Stars1330 Nearby FGKM Stars
(~2000 stars total with Mayor et al. )(~2000 stars total with Mayor et al. )
Star Selection Criteria:Star Selection Criteria:
•Vmag < 10 mag• No Close Binaries• Age > 2 Gyr
Hipparcos Cat. d < 100 pc
Lum
1.3Msun
0.3 MSUN
.. 1330 Target Stars 1330 Target Stars
Target List:Target List:PublishedPublished
H-R DiagramH-R Diagram
22
Michel Mayor & DidierMichel Mayor & Didier Queloz Queloz
51 Peg51 Peg
First First ExoPlanetExoPlanet
Now Now Stephane Udry Stephane Udry plays leadership role also.plays leadership role also.
2000 FGKM M.S. Stars2000 FGKM M.S. StarsThree TelescopesThree Telescopes
19 Years19 Years(6 AU)(6 AU)
LickLick
8 Years8 Years (3.5 AU)
7 Years7 Years (3 AU)
Uniform Doppler Precision: 1-3 m sUniform Doppler Precision: 1-3 m s-1-1Doppler Doppler Monitering Monitering Begun: 1987Begun: 1987
Anglo-Aus. Tel.Anglo-Aus. Tel.KeckKeck
33
Precision: 1.5 m sPrecision: 1.5 m s-1-1
3 Years3 Years
Planets or Brown DwarfsPlanets or Brown Dwarfsin Unclosed, Long-Period Orbits:in Unclosed, Long-Period Orbits:
Targets for CoronagraphsTargets for Coronagraphs
44
SepSep ~~ 0.3 0.3 ““
SepSep ~ 0.2 ~ 0.2 ““
55
Sep ~ 0.2Sep ~ 0.2””
Examples ofExamples ofJupiter-massJupiter-mass
&&Saturn massSaturn mass
Planets Detected Planets Detected by RVby RV
66
Jupiter MassJupiter Mass Extrasolar Extrasolar PlanetsPlanets
P = 5.3 yrP = 5.3 yre = 0.47e = 0.47
Jupiter MassJupiter Mass Extrasolar Extrasolar PlanetsPlanets
P = 1.3 yrP = 1.3 yr
77
Msini Msini = 32 = 32 MMEarthEarth
Msini Msini = 57 = 57 MMEarthEarth
Msini Msini = 37 = 37 MMEarthEarth
Sub-Saturn Masses: Sub-Saturn Masses: 30 - 100 30 - 100 MMEarthEarth
Old Doppler Precision: 3 m/sOld Doppler Precision: 3 m/s
Sub-Saturn Masses:Sub-Saturn Masses: Detectable for P < 2 MonthDetectable for P < 2 Month
Multiple - Planet SystemsMultiple - Planet Systems
88
Weak Interactions2.5 MJ1.9 MJ
HD 12661: Sun-like StarHD 12661: Sun-like Star
2 - Planet Model2 - Planet Model
Velo
city
(m
eter
s/se
c)
Time (years)
HD 128311HD 128311 2:1 Resonance 2:1 Resonance
Inner OuterInner OuterPer (d)Per (d) 458 918 458 918MMsinisini 2.3 3.12.3 3.1ecc ecc 0.23 0.23 0.22 0.22ωω 119 119 212 212
PPc c / / PPbb = 2.004= 2.004Dynamical ResonanceDynamical Resonance(Laughlin)(Laughlin)
K0V, 1Gy, 16 pcK0V, 1Gy, 16 pc
99
Msini Msini = 1.4 M= 1.4 MJJ
M Dwarfs haveM Dwarfs have distant giant planets.distant giant planets.
5 Mean-Motion5 Mean-MotionResonancesResonances
Implies:Implies: Orbital MigrationOrbital Migration Capture intoCapture into
ResonancesResonances Eccentrcity Eccentrcity PumpingPumping
CoronagraphsCoronagraphs cancanexpect expect planets at 20 AUplanets at 20 AUaccompanied byaccompanied byinner giant planetsinner giant planets
1010
Giant Planets:Giant Planets: Mass Distribution Mass Distribution
Detection Limit:Detection Limit:~ 0.2 M~ 0.2 MJUP JUP @ 1 AU@ 1 AU
Rise towardRise toward lower masseslower masses
to 1 Mto 1 MSATSAT
Sub-SaturnsSub-Saturns
13/138 have13/138 haveMMplpl > 5 M> 5 MJJ= 10% of planets= 10% of planets
Poor
Detect-
ability
IfIf ddN N / / ddllogog a = const:a = const: ΔΔ6% of stars have6% of stars have planets planets 3 - 20 AU .3 - 20 AU .
LogLog
Semimajor Semimajor AxisAxis DistributionDistribution 6.5 % 6.5 % OccurrenceOccurrence
12 % of stars12 % of starsHarborHarborGiant PlanetsGiant Planets
1111
OrbitalOrbital Period DistributionPeriod DistributionCorrection for IncompletenessCorrection for Incompleteness
Period (days)Period (days)
Num
ber
Num
ber
dN /dlog dN /dlog P ~ PP ~ Pββ
ββ = +0.26 = +0.26
Cumming et al. 2007Cumming et al. 2007
27 yr27 yr9 AU9 AU
dN/dlogdN/dlog1010PP = 6.5%= 6.5%
Take Home:Take Home:
Occurrence of Long Period OrbitsOccurrence of Long Period OrbitsCumming et al. 2007Cumming et al. 2007
a < 3 AU 5 AU a < 3 AU 5 AU 10 AU 20 AU10 AU 20 AU
8.5% 8.5% 11% 11% 14% 19%14% 19%
For: 0.3 < For: 0.3 < MMplpl < 15 M< 15 MJJ
Cumulative percentage of stars with a Cumulative percentage of stars with a palnetpalnetN (<P), based on a power law extrapolation beyond P = 2000 d.N (<P), based on a power law extrapolation beyond P = 2000 d.
1212
Poor
Detect-
ability
IfIf ddN N / / ddllogog a = const:a = const: ΔΔ6% of stars have6% of stars have planets planets 3 - 20 AU .3 - 20 AU .
Most Models ==> Most Models ==> Reservoir of Reservoir of Jupiters Jupiters at 5-20 AU.at 5-20 AU.
Few Few Jupiters Jupiters a> 20 AU.a> 20 AU.LogLog
Semimajor Semimajor AxisAxis DistributionDistribution 6.5 % 6.5 % OccurrenceOccurrence
If If dN/dloga dN/dloga = const,= const,6%6% 20-120 AU20-120 AU
Inward Migration.Inward Migration. Planets left in placePlanets left in place as disk vanishes .as disk vanishes .
ArmitageArmitage,, Livio Livio,, Lubow Lubow, Pringle (2002), Pringle (2002)Trilling, Benz,Trilling, Benz, Lunine Lunine (2002)(2002)Lin & Ida 2004Lin & Ida 2004Alibert Alibert & Benz& Benz
Spectral SynthesisModeling
1) LTE radiative transferwith Kurucz modelatmospheres.
2) Least-Squares fit tospectral lines.
ChemicalChemicalAbundancesAbundancesOf StarsOf StarsFischer &Fischer & Valenti Valenti
1313
Planet Planet –– Metalicity Metalicity CorrelationCorrelation
Chem.Abund.Analysis of1000 stars onplanet search .
22PPplanetplanet ~ ~ ((NN
FeFe/ N/ N
HH))
Previous Planet-Previous Planet-Metallicity CorrMetallicity Corr::G.Gonzales, N.SantosG.Gonzales, N.Santos
Fischer & Fischer & Valenti Valenti 20052005
Metalicity Metalicity Models:Models:Core-Accretion Model:Core-Accretion Model:More Dust -->More Dust -->Planet growth ratePlanet growth rateIda & Lin (2005)Ida & Lin (2005) Kornet Kornet et al. (2005)et al. (2005) Ed Ed Thommes Thommes 20062006
Exoplanets Exoplanets as a function ofas a function ofStellar MassStellar Mass
- 120 M dwarfs (0.3-0.6 M- 120 M dwarfs (0.3-0.6 MOO)) - - 200 200 ““A-typeA-type”” Stars Stars (1.5-2.0 M(1.5-2.0 MOO))
1414
Retired A-Stars and Their PlanetsRetired A-Stars and Their Planets
John Johnson et al. (2007)
HD 210702: HD 210702: MM** = 1.85 M = 1.85 M
John Johnson 2007John Johnson 2007
1515
Jupiter Occurrence Jupiter Occurrence vs vs Stellar MassStellar MassFor a < 2.0 AU, Mpsini > 0.8 MJup, Nobs > 8
5/58 @Lick
3/31 @Keck
InclIncl. . SubgiantsSubgiants::1.5-2.5 1.5-2.5 M_sunM_sun
BewareBewareMetallicityMetallicityEffects.Effects.
JohnJohnJohnsonJohnson20072007
Orbital EccentricitiesOrbital Eccentricities
<e> = 0.25<e> = 0.25 Origin of Origin of eccenteccent.. controversial .controversial .
Ecc Ecc still highstill high
beyondbeyond 2.5 AU 2.5 AU
<e>=0.25<e>=0.25
Tidal Circ.:Tidal Circ.: a < 0.1 AU a < 0.1 AU
1616
Origin of EccentricitiesOrigin of EccentricitiesPlanet - Planet InteractionsPlanet - Planet Interactions
Ford & Ford & Rasio Rasio 20062006
Super-Earths: 1 - 14 Super-Earths: 1 - 14 MMEarthEarthPoorly Understood Planet DomainPoorly Understood Planet Domain
Earth - Uranus:Earth - Uranus: Gap in Mass: Factor 14 Gap in Mass: Factor 14
Intermediate MassesIntermediate Masses::
Do theyDo they Form?Form? Or do planet embryosOr do planet embryos accrete gas ala Neptune ?accrete gas ala Neptune ?
If They Form:If They Form: - - TerrTerr-like: CO-like: CO22 AtmAtm. ?. ? - Neptune-like H&He - Neptune-like H&He env env ??
Density: Density: 1 or 5 g cm1 or 5 g cm-3 -3 ??
Terrestrial
Ice & Gas giantsIce & Gas giants
Super-Super-EarthsEarths
??
1717
Gliese Gliese 436 (M2.5 V)436 (M2.5 V)
Gl Gl 436:436: Periodogram Periodogram
P = 2.643 dayP = 2.643 day
1818
Gliese Gliese 436:436:
22 Earth Masses22 Earth Masses
MsinMsinii = 22 M= 22 MEarthEarth
Tidal LockTidal Lock P = 2.64 dP = 2.64 d
Composition ?Composition ? Gaseous ? Gaseous ? Rock + ice ? Rock + ice ? Rock + Fe core? Rock + Fe core?
LLSTARSTAR= 1/50 L= 1/50 LOO
Atmosphere?Atmosphere? T Tfrontfront = 650 K ?= 650 K ? TTbackback< 200 K ?< 200 K ?
..
Butler et al. 2004; Maness et al. 2007Butler et al. 2004; Maness et al. 2007
Gliese Gliese 436 Transits436 TransitsR = 3.95 R = 3.95 RREarthEarth
Gillon Gillon et al 2007et al 2007
pp
ρρ = 2.0 gm/cc = 2.0 gm/cc
1919
Model from Fortney, Marley, & Jones 2007Model from Fortney, Marley, & Jones 2007
or liquid?
ρρ = 2.0 gm/cc = 2.0 gm/cc
Possible:Possible:Rocky coreRocky core&&H/He H/He EnvEnv..
Requires unlikely Requires unlikely 17 17 M_Earth of rockM_Earth of rockwithin 1 AU.within 1 AU.
““It seems likely that planets with masses within an order ofIt seems likely that planets with masses within an order ofmagnitude of the Earthmagnitude of the Earth’’s mass will be composed primary ofs mass will be composed primary of……ices, rocks, and iron.ices, rocks, and iron.””
Gliese Gliese 876 (M3V)876 (M3V)
Star Mass = 0.32 Star Mass = 0.32 MMsunsun
d = 4 pcd = 4 pc Two Two JupitersJupiters in 2:1 in 2:1 resres..
2020
Gliese Gliese 876: 2-Planet Fit876: 2-Planet FitVe
loci
ty (
m s
Ve
loci
ty (
m s
-1-1 ) )
TimeTime
GL 876GL 8762:1 Mean-Motion Resonance2:1 Mean-Motion Resonance
&&Apsidal LockApsidal Lock
Inner Outer Inner OuterPP 30.1 61.0 d 30.1 61.0 dMsiniMsini 0.56 1.89 M0.56 1.89 MJJ
ee 0.27 0.10 0.27 0.10
ωω 330 333 330 333οο
Resonance Work: Laughlin & Chambers Lissauer & Rivera Man Hoi Lee & S.Peale
2121
Gliese Gliese 876876
2:12:1Mean MotionMean Motion
ResonanceResonance
PrecessionPrecessionPeriod: 9 yrPeriod: 9 yr
Man Hoi LeeMan Hoi Lee
GJ 876: VelocitiesGJ 876: Velocities Two-PlanetTwo-PlanetModelModel
Laughlin et al. 2004
2222
3-Planet Fit3-Planet Fit
Rivera &Rivera &LissauerLissauer
Velocity Residuals toVelocity Residuals to2-Planet fit2-Planet fit
Period = 1.94 dPeriod = 1.94 d
M M sinsinii = 5.9 = 5.9 MMEarthEarth
For i = 50 deg,For i = 50 deg,MMPLPL = 7.5 = 7.5 MMEarthEarthVe
loci
tyVe
loci
ty
Orbital PhaseOrbital PhaseInward oInward off habitable zonehabitable zone
2323
Gliese Gliese 581581 Orbit Orbit Min.Mass Min.Mass Likely Mass (x 4/Likely Mass (x 4/ππ)) Radius(AU) Radius(AU) (Earths) (Earths) (Earths)(Earths)------------------------------------------------------------------------------------------ b 0.041 b 0.041 15.2 15.2 19 19 c c 0.073 0.073 5.0 5.0 6.46.4 ””T = 0-40 CT = 0-40 C”” d d 0.25 0.25 8.2 8.2 10.410.4--------------------------------------------------------------------------------------------
Planet Planet ““cc”” ::1) Actual Habitable Zone:1) Actual Habitable Zone: 0.10-0.20 AU0.10-0.20 AU Efficient IR opacity -> heating inEfficient IR opacity -> heating in any atmosphere (any atmosphere (SasselovSasselov, , SelsisSelsis,, KastingKasting, , SeagerSeager, , BlohBloh, , CuntzCuntz, 2007), 2007) (Potsdam preprint)(Potsdam preprint)
2) 2) Mass: Arguably an Ice Giant:Mass: Arguably an Ice Giant:~ ~ Gliese Gliese 436 b, Uranus, Neptune436 b, Uranus, Neptune
See Xavier See Xavier Bonfils Bonfils talk.talk.
2424
In a In a protoplanetary protoplanetary disk,disk,ifif 6 6 MMearth earth of silicates accumulate into planetof silicates accumulate into planet
does itdoes it normally acquire ices too?normally acquire ices too?
Outside snow line: Outside snow line: Yes.Yes.
Witness Solar SystemWitness Solar System’’s - s - icy giants, icy moons, icy giants, icy moons, plutopluto, , KBOsKBOsAllAll have comparablehave comparable:: silicate & water silicate & water
Formation Within Snow Line:Formation Within Snow Line:Water Delivery to Rocky PlanetsWater Delivery to Rocky Planetsby hydrated asteroids & cometsby hydrated asteroids & comets
Water Delivery: Comets &Water Delivery: Comets &hydrated asteroidshydrated asteroids
HH22O contentO content vs r vs rorborb fromfrommeteoritesmeteorites
N-body: collisions deliver HN-body: collisions deliver H22OO Jupiter ejects asteroids,Jupiter ejects asteroids,
preventing their delivery of waterpreventing their delivery of waterto the terrestrial planets at 1 AU.to the terrestrial planets at 1 AU.
Continuous HContinuous H22O deliveryO delivery Loss of HLoss of H22O by impacts ? ? ?O by impacts ? ? ?
Water-rich worlds common ?:Water-rich worlds common ?: 10 - 100 10 - 100 ““Earth-OceansEarth-Oceans””
N-Body Planet Growth with Water DeliveryN-Body Planet Growth with Water DeliveryRaymond, Quinn, Raymond, Quinn, Lunine Lunine 20042004
Water Content (Earth Oceans)Water Content (Earth Oceans)
2525
Solve Interior Solve Interior EqnsEqns.. Include EOS of water +Include EOS of water +
Rock mantle + Fe coreRock mantle + Fe core Water is Water is liquidliquid at high at high
pressure (pressure (~Europa~Europa) .) .
Phase Diagram of WaterPhase Diagram of Water
Super EarthsSuper EarthsFormationFormation beyondbeyond 2 AU2 AU
Leger et al. 2004Leger et al. 2004
Ice-rock Ice-rock planetesimal planetesimal growthgrowth Europa Europa/Neptune Composition:/Neptune Composition:
Ice - rock : 50-50Ice - rock : 50-50 Migration inward of 1 AUMigration inward of 1 AU
StructureStructure
10 - 50% H10 - 50% H22OO
HH22O Atmosphere +O Atmosphere + HH22O Ocean +O Ocean + Ice Envelope (ala Neptune) Ice Envelope (ala Neptune)
Lower Density than rocky planetsLower Density than rocky planets
Distinguish water worlds from rockyDistinguish water worlds from rockyworlds:worlds:
Radial velocity and transit ---> M Radial velocity and transit ---> M, R ., R .
oceanocean
66 M MEarthEarth Planets:Planets:50% H50% H22O O No H No H22OO
Fe, Ni
Silicates
““iceice””
ρρ = 4.3 g cm = 4.3 g cm-3-3 ρρ = 7.7 g cm = 7.7 g cm-3-3
PPcc = 1600 = 1600 GPaGPa
ss
Leger 2004, Raymond 2005Leger 2004, Raymond 2005
2626
Detecting Detecting Rocky PlanetsRocky Planetsby Doppler Measurements of Starsby Doppler Measurements of StarsStarStar’’s Wobble Velocity:s Wobble Velocity: K = 0.1 m/s [K = 0.1 m/s [MMplpl/M/Mstar star 1/a1/aAUAU
1/21/2]] ((MMplpl in Min MEE))
Benchmark:Benchmark: Earth induces 0.1 m/s (at 1 AU)Earth induces 0.1 m/s (at 1 AU)
Strategy:Strategy: Achieve Doppler Precision of 1 m/sAchieve Doppler Precision of 1 m/s Choose Low Mass StarsChoose Low Mass Stars Search for Short Periods (small a)Search for Short Periods (small a) Low mass stars haveLow mass stars have lower surface turbulence and lower oscillationslower surface turbulence and lower oscillations
Lyot Lyot ConferenceConference
SummarySummary Mass Distribution: Rises to lower massesMass Distribution: Rises to lower masses Semimajor Semimajor Axis Axis DistribDistrib.: Rises toward 5 AU - Beyond?.: Rises toward 5 AU - Beyond? Planets correlate withPlanets correlate with Metalicity Metalicity & Stellar mass& Stellar mass
Concern:Concern: <5% have giant planets beyond <5% have giant planets beyond 20 AU20 AU ~10%~10% of giant planets haveof giant planets have M>5 M>5 MjupMjup
Occurrence of M>5 Occurrence of M>5 Mjup Mjup beyond 20 AU < 0.5% ??beyond 20 AU < 0.5% ??
F and A starsF and A stars gold vein: Young, Massive, Metal-Rich Starsgold vein: Young, Massive, Metal-Rich Stars