and intelligent life in the universe
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And Intelligent Life in the Universe
The Occurrence of Planetsand
Mass-Radius Relationfrom Kepler
Keck
Tel Aviv7 December 2012
Kepler
Thanks to:Shay Zucker
Amiel Sternberg
Geoff MarcyUniversity of California
And Intelligent Life in the Universe
The Occurrence of Planetsand
Mass-Radius Relationfrom Kepler
Keck
Tel Aviv7 December 2012
Kepler
Tsevi MazehThanks to:
Shay ZuckerAmiel Sternberg
AcknowledgementsWilliam BoruckiDavid KochStephen BrysonJason RoweRoger Hunter Marcie Smith Susan ThompsonBruce ClarkRob LewisGuillermo TorresFrancois FressinJean-Michel DésertLars BuchhaveSam QuinnDan FabryckyDebra FischerDimitar Sasselov
Natalie BatalhaThomas GautierSteve HowellCharlie SobeckTsevi MazehDavid LathamFergal MullallyJoe TwickenElisa QuintanaRon GillilandEric FordElliott HorschTom BarclayJessie ChristiansenJack Lissauer
Jon JenkinsMike HaasDoug CaldwellJeff KolodziejcakMartin StillShawn SeaderJie LiDavid CharbonneauDavid CiardiChris Burke Leslie RogersMartin StillMartin StumpePeter TenebaumLucianne WalkowiczBill CochranMike Endl
Kepler’s Heavy Lifters
Andrew Howard, Lauren Weiss, Howard Isaacson, Jason Rowe, John JohnsonSpecial Thanks:
AcknowledgementsWilliam BoruckiDavid KochStephen BrysonJason RoweRoger Hunter Marcie Smith Susan ThompsonBruce ClarkRob LewisGuillermo TorresFrancois FressinJean-Michel DésertLars BuchhaveSam QuinnDan FabryckyDebra FischerDimitar Sasselov
Natalie BatalhaThomas GautierSteve HowellCharlie SobeckTsevi MazehDavid LathamFergal MullallyJoe TwickenElisa QuintanaRon GillilandEric FordElliott HorschTom BarclayJessie ChristiansenJack Lissauer
Jon JenkinsMike HaasDoug CaldwellJeff KolodziejcakMartin StillShawn SeaderJie LiDavid CharbonneauDavid CiardiChris Burke Leslie RogersMartin StillMartin StumpePeter TenebaumLucianne WalkowiczBill CochranMike Endl
Kepler’s Heavy Lifters
Jupiter-size
Neptune-size
Earth-size
Orbital Period in days
Size
Rel
ativ
e to
Ear
th
5
2300 Small Exoplanets
Jupiter-size
Neptune-size
Earth-size
Orbital Period in days
Size
Rel
ativ
e to
Ear
th
6
2300 Small Exoplanets
Earth-SizeClose-in
Multiple Transits yield sufficient S/N Ratio for detection.
Data binning yields obvious transit signatures
Francois Fressin et al. 2012
Kepler: Hundreds of Earth-size Planets – in Tight Orbits
0.87 R
1.03 R
+
+
P = 6.098 days
P = 19.577 days
Brig
htne
ssBr
ight
ness
Jupiter-size
Neptune-size
Earth-size
Orbital Period in days
Size
Rel
ativ
e to
Ear
th
8
2300 Small Exoplanets
R=1-4 REarth
- Not in S.S. - Interior: Rock + ? - Formation ?
Define Planet OccurrenceFor each RPL and Period:
Define Planet OccurrenceFor each RPL and Period:
Define the Stellar Domain:Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence
Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
Define the Survey Domain:Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
Note: Only 59,000 Kepler Target stars meet these stellar criteria
Define the Survey Domain:Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
SNR Threshold of Transit: 10 Demand SNR > 10 in Quarter 3
Note: Only 59,000 Kepler Target stars meet these stellar criteria
Define the Survey Domain:Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
SNR Threshold of Transit: 10 Demand SNR > 10 in Quarter 3
SNR Depends on • planet radius • # of transits• Photometric noise
Note: Only 59,000 Kepler Target stars meet these stellar criteria
15
Number of Target Stars Capable of AchievingSNR > 10 in Quarter 3
magTarget Star Parameters: Teff=4100-6100 K, log g=4.0-4.9, Kepmag<15Pl
anet
Rad
ius [
R Ear
th]
Howard, Marcy, Kepler Team. (2011)
Define Planet OccurrenceFor each RPL and Period:
17Howard, Marcy, Kepler Team (2011)
18Howard, Marcy, Kepler Team (2011)
19Howard, Marcy, Kepler Team (2011)
20Howard, Marcy, Kepler Team (2011)
21
Focus on a single domain In Period and Radius
Howard, Marcy, Kepler Team (2011)
22
Naïve: Count the planets in this domain.
Focus on a single domain In Period and Radius
Howard, Marcy, Kepler Team (2011)
23
Focus on a single domain In Period and Radius
Howard, Marcy, Kepler Team (2011)
Naïve: Count the planets in this domain.
Best: Augment each planet by its # of “inclined” twins: a/RSTAR .
Augment Each Transiting Planet by the# of (undetected) Inclined Twins
# Planets at All Inclinations = a / RSTAR
aRSTAR
25
Focus on a single domain In Period and Radius
Howard, Marcy, Kepler Team (2011)
Naïve: Count the planets in this domain.
Best: Augment each planet by # of “inclined” twins: a/RSTAR:
26
Focus on a single domain In Period and Radius
Howard, Marcy, Kepler Team (2011)
Naïve: Count the planets in this domain.
Best: Augment each planet by # of “inclined” twins: a/RSTAR: Typically 5-20.
Define Planet Occurrencewithin each cell:
Distribution of Planet RadiiFor Orbital Periods < 50 Days
Howard, Marcy, Kepler Team, as of Sept. 2011
8% of G starshave a planet of2.0-2.8 REarth
10% of stars havePlanets 2.0-2.8 REarth.
1% of stars havePlanets 8-11 REarth.
Howard et al. Analysis:
Redone with Planet Candidates
through Quarter 6from Batalha et al. 2012
Distribution of Planet Sizes
Petigura, Howard, Marcy, Kepler Team - Nov 2012
Is Declineto 1 REarth
Real ?
Jupiter-size
Neptune-size
Earth-size
Orbital Period in days
Size
Rel
ativ
e to
Ear
th
31
2300 Small ExoplanetsBatalha et al. 2012
Earth-Size: Not many…
Distribution of Planet Sizes
Petigura, Howard, Marcy, Kepler Team - Nov 2012
Is Declineto 1 REarth
Real ?
Or is it due toIncompleteness inThe Kepler pipeline?
SNR (SES) ~ 1 for R=1 REarth
New Kepler Pipelineby Erik Petigura
• New CBVs• New Search Algorithm
Petigura’s Kepler PiplineAdopted CDPP Threshold: “Best 12,000 Kepler Stars”
Best 12000
Planets Detectedin “Best 12000” Kepler Stars
Petigura et al. 2013
Now:- Assess completeness- Compute occurrence ala Howard et al.
Completeness Measurement
Petigura et al. 2013
Detection Completeness: > 80%
- Radius = 1.2 – 4 REarth
- Period > 50 d
Inject Mock Transits into Actual Kepler Raw photometery
Planets Detectedin “Best 12000” Kepler Stars
Petigura et al. 2013
Now makeSame correctionsAs in Howard et al.
Fressin et al. Occurrence
Occurrence isFlat Shortwardof 2 REarth
Agreement withPetigura & Howard
39
Mass-Radius Diagram
246
104
32120b
20c
Planet Mass-Radius Diagram
Kepler Planet Masses and RadiiKOI-94
KOI-94 Photometry:4 Transiting Planets
P=3.74 dR=1.7 RE
P=10.42 dR=4.3 RE
P=22.34 dR=11.3 RE
P=54.32 dR=6.56 RE
Lauren Weiss et al. 2013
Doppler Measurements of KOI-94:Masses for two planets.Only Upper limits for two.
Lauren Weiss et al. 2013
135 Exoplanets with Mass and Radius
Planet Radius vs Mass
• Two mass domains: MCRIT = 150 MEARTH
• Affect of stellar Flux on Planet:• M>150 MEARTH: Bloated• M<150 MEARTH: Smaller
Weiss, Marcy, et al. 2013
Planet Radius vs Mass
Weiss, Marcy, et al. 2013
Planet Radius vs Mass
Planet Radius vs MassConstant Density:R ~ M1/3
Radius rises fasterthan solid interior!
Implication:Admixture ofmore volatiles withIncreasing mass.
i.e. Water or H + He.
Planet Radius vs Mass
Planet Radius vs MassPlanet Radius vs Mass
Planet Radius vs MassPlanet Radius vs Mass
Electron Degeneracy:R ~ M-1/3
Radii rises fasterThan e- degeneracy.
Implication:Admixture ofmore volatiles withIncreasing mass.
i.e. Water or H + He.
Planet Density vs Mass
Planet Density vs Mass
Models:Mordasini et al.Chiang & Laughlin:Rock + Gas
Up next: Habitable Zone Earths
Jupiter-size
Neptune-size
Earth-size
Orbital Period in days
Size
Rel
ativ
e to
Ear
th
Extended missiondomain Earth
analogs
53
2300 Small Exoplanets
• Planet R(M,Flux) becoming defined. • Two Domains: Critical Mass at 150 MEarth • Radii increase faster with Mass than Expected::
Amt. of Volatiles increases with mass.• Planet Occurrence: Rises from 20-2 REarth
Flat from 2.0–1.2 REarth
• Questions: -Interiors 2-4 REarth and 1-2 REarth -Occurrence of Planets from 2 – 0.5 REarth
Summary
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