COMBINING ASTEROSEISMOLOGYAND EXOPLANETS PLATO MISSION CONFERENCE 2017
VINCENT VAN EYLEN
JAN HENDRIK OORT FELLOW –LEIDEN OBSERVATORY Exoplanet person surrounded by asteroseismologists...
Turns out people were thinking about this for 30 years!
sci.esa.int/plato/ But also: 1 Stellar obliquities, through rotational splittings
2 Orbital eccentricities, through mean stellar densities
3 Evolution of planetary systems, through e.g. tides
All have given exciting results with Kepler/K2, and will be order(s) of magnitude better with PLATO.
What asteroseismology can do for exoplanets
Accurate planet parameters, through accurate stellar parameters (Including planet validation!) What asteroseismology can do for exoplanets
Accurate planet parameters, through accurate stellar parameters (Including planet validation!)
But also: 1 Stellar obliquities, through rotational splittings
2 Orbital eccentricities, through mean stellar densities
3 Evolution of planetary systems, through e.g. tides
All have given exciting results with Kepler/K2, and will be order(s) of magnitude better with PLATO. Planetary migration? (e.g. Rasio & Ford 1996, Matsumura et al. 2010, Fabrycky & Tremaine 2007) Primordial star-disk misalignment? (e.g. Bate et al. 2010, Thies et al. 2011, Batygin 2012) x Obliquity measurements in multi-(small-)planet systems ⇒
How to explain observed stellar obliquities?
Courtesy Josh Winn
Hot Jupiters display a wide range of obliquities, e.g.: Winn et al. 2010 Schlaufman 2010 H´ebrard et al. 2011 Albrecht et al. 2012 How to explain observed stellar obliquities?
Courtesy Josh Winn
Hot Jupiters display a wide range of obliquities, e.g.: Winn et al. 2010 Schlaufman 2010 H´ebrard et al. 2011 Albrecht et al. 2012
Planetary migration? (e.g. Rasio & Ford 1996, Matsumura et al. 2010, Fabrycky & Tremaine 2007) Primordial star-disk misalignment? (e.g. Bate et al. 2010, Thies et al. 2011, Batygin 2012) x Obliquity measurements in multi-(small-)planet systems ⇒ Time series power spectrum. ⇒ i =45 ◦ 0.5 i =82.5 ◦ (best fit)
0.4 ] 2 0.3
0.2 Power [ppm
l=1 l=0 0.1 m= -1 0 1 l=2
0.0 1920 1940 1960 1980 2000 2020 Frequency [µHz]
Van Eylen et al. 2014
Example: multi-planet system Kepler-410 i =45 ◦ 0.5 i =82.5 ◦ (best fit)
0.4 ] 2 0.3
0.2 Power [ppm
l=1 l=0 0.1 m= -1 0 1 l=2
0.0 1920 1940 1960 1980 2000 2020 Frequency [µHz]
Example: multi-planet system Kepler-410 Time series power spectrum. ⇒
Van Eylen et al. 2014 i =45 ◦ 0.5 i =82.5 ◦ (best fit)
0.4 ] 2 0.3
0.2 Power [ppm
l=1 l=0 0.1 m= -1 0 1 l=2
0.0 1920 1940 1960 1980 2000 2020 Frequency [µHz]
Example: multi-planet system Kepler-410 Time series power spectrum. ⇒
Van Eylen et al. 2014 Example: multi-planet system Kepler-410 Time series power spectrum. ⇒ i =45 ◦ 0.5 i =82.5 ◦ (best fit)
0.4 ] 2 0.3
0.2 Power [ppm
l=1 l=0 0.1 m= -1 0 1 l=2
0.0 1920 1940 1960 1980 2000 2020 Frequency [µHz]
Van Eylen et al. 2014 Obliquities?
Albrecht et al. 2013 Obliquities?
Albrecht et al. 2013, adapted by Huber 2017, including data from Sanchis-Ojeda et al. 2012, Hirano et al. 2012 Chaplin et al. 2013, Huber et al. 2013, Van Eylen et al. 2014, Benomar et al. 2014
1 Single-planet systems (grey): a wide range 2 Multi-planet systems (color): flatter obliquity distribution (?) Green points from asteroseismology! Waiting for PLATO...
Ensemble studies: e.g. Morton & Winn 2014, Mazeh et al. 2015, Campante et al. 2016 Eccentricities?
1.0 Solar system 0.8
0.6
0.4 Eccentricity 0.2
0.0 10-2 10-1 100 101 102 103 104 Mass [M ] ⊕
Eccentricities from RV detections from exoplanets.org (27 April ’15). Eccentricities?
1.0 Solar system RV planets 0.8
0.6
0.4 Eccentricity 0.2
0.0 10-2 10-1 100 101 102 103 104 Mass [M ] ⊕
Eccentricities from RV detections from exoplanets.org (27 April ’15). Eccentricities?
1.0 Solar system RV planets 0.8
0.6
0.4 Eccentricity 0.2
0.0 10-2 10-1 100 101 102 103 104 Mass [M ] ⊕
Eccentricities from RV detections from exoplanets.org (27 April ’15). How to observe eccentricity?
1 2
+ 2 Radial Velocity [m/s] - 1
Time How to observe eccentricity?
1 2
+ 2 Radial Velocity 1 [m/s] -
Time Transit timing variations (e.g. Hadden & Lithwick 2014) Occultation timing (Shabram et al. 2015) Transit durations!
(1+e sin ω)3 Transit duration ρ? ∝ (1−e2)3/2 measure the stellar density ρ? (asteroseismology) ⇒ marginalize over unknown orientation ω ⇒
Small planets: no RV possible. Eccentricity? Occultation timing (Shabram et al. 2015) Transit durations!
(1+e sin ω)3 Transit duration ρ? ∝ (1−e2)3/2 measure the stellar density ρ? (asteroseismology) ⇒ marginalize over unknown orientation ω ⇒
Small planets: no RV possible. Eccentricity? Transit timing variations (e.g. Hadden & Lithwick 2014) Transit durations!
(1+e sin ω)3 Transit duration ρ? ∝ (1−e2)3/2 measure the stellar density ρ? (asteroseismology) ⇒ marginalize over unknown orientation ω ⇒
Small planets: no RV possible. Eccentricity? Transit timing variations (e.g. Hadden & Lithwick 2014) Occultation timing (Shabram et al. 2015) (1+e sin ω)3 Transit duration ρ? ∝ (1−e2)3/2 measure the stellar density ρ? (asteroseismology) ⇒ marginalize over unknown orientation ω ⇒
Small planets: no RV possible. Eccentricity? Transit timing variations (e.g. Hadden & Lithwick 2014) Occultation timing (Shabram et al. 2015) Transit durations! Small planets: no RV possible. Eccentricity? Transit timing variations (e.g. Hadden & Lithwick 2014) Occultation timing (Shabram et al. 2015) Transit durations!
(1+e sin ω)3 Transit duration ρ? ∝ (1−e2)3/2 measure the stellar density ρ? (asteroseismology) ⇒ marginalize over unknown orientation ω ⇒ 28 multi-planet systems with 74 planets (ρ? from Huber et al. 2013, Silva Aguirre et al. 2015) ?
1.0 Solar system RV planets 0.8
0.6
0.4 Eccentricity 0.2
0.0 10-2 10-1 100 101 102 103 104 Mass [M ] ⊕ 28 multi-planet systems with 74 planets (ρ? from Huber et al. 2013, Silva Aguirre et al. 2015)
1.0 Solar system RV planets 0.8 Multi-planet systems Van Eylen & Albrecht 2015 0.6
0.4 Eccentricity 0.2
0.0 10-2 10-1 100 101 102 103 104 Mass [M ] ⊕
Rayleigh distribution with σ = 0.049 0.013 ± 50 single transiting planets (ρ? from Lundkvist et al. 2016)
1.0 Solar system RV planets 0.8 Multi-planet systems Van Eylen & Albrecht 2015 Single-planet systems 0.6 Van Eylen et al. (in prep.)
0.4 Eccentricity 0.2
0.0 10-2 10-1 100 101 102 103 104 Mass [M ] ⊕
Rayleigh distribution with σ = 0.36 0.11 ± (Some) single transiting planets have higher eccentricity.
7 Single Transiting Planet 6 Multi-planets (Van Eylen & Albrecht 2015)
5
4
3 Density 2
1
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Eccentricity
Van Eylen et al. 2017, in prep.
“Two types” of planetary systems (“Kepler dichotomy”)? Non-transiting inclined planets? Perturbing giants?
Waiting for PLATO bright stars... Eccentricity of binary stars!
t1 = 2.112 Porb/2 t2 = 6.566
1.00
0.98
0.96
0.94
Normalized flux 0.92 0 1 2 3 4 5 6 7 8 9 Time [d]
1.00 1.00
0.98 0.98
0.96 0.96
0.94 0.94
Normalized flux 0.92 0.92 2.0 2.1 2.2 2.3 6.4 6.5 6.6 6.7 Time [d] Time [d]
Van Eylen, Winn & Albrecht 2016
What about tides? t1 = 2.112 Porb/2 t2 = 6.566
1.00
0.98
0.96
0.94
Normalized flux 0.92 0 1 2 3 4 5 6 7 8 9 Time [d]
1.00 1.00
0.98 0.98
0.96 0.96
0.94 0.94
Normalized flux 0.92 0.92 2.0 2.1 2.2 2.3 6.4 6.5 6.6 6.7 Time [d] Time [d]
Van Eylen, Winn & Albrecht 2016
What about tides? Eccentricity of binary stars! What about tides? Eccentricity of binary stars!
t1 = 2.112 Porb/2 t2 = 6.566
1.00
0.98
0.96
0.94
Normalized flux 0.92 0 1 2 3 4 5 6 7 8 9 Time [d]
1.00 1.00
0.98 0.98
0.96 0.96
0.94 0.94
Normalized flux 0.92 0.92 2.0 2.1 2.2 2.3 6.4 6.5 6.6 6.7 Time [d] Time [d]
Van Eylen, Winn & Albrecht 2016 What about tides? Eccentricity of binary stars!
1.0
0.8
0.6
0.4
0.2
0.0
Percentage of eccentric0.2 orbits per bin 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Log(10) P
Van Eylen, Winn & Albrecht 2016 What about tides? Eccentricity of binary stars!
1.0 180
0.8 150
120 0.6 90 0.4 60 proj. obliquity [deg]
0.2 30
0 0.0 Percentage of eccentric0.2 orbits per bin 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 5000 6000 7000 8000 Log(10) P Teff [K]
Van Eylen, Winn & Albrecht 2016, ApJ Winn et al. 2010, Albrecht et al. 2012 What about tides? Eccentricity of binary stars!
Cool-cool Hot-cool Hot-hot 1.0 180
0.8 150
120 0.6 90
0.4 60 proj. obliquity [deg]
0.2 30
0 0.0 Percentage of eccentric orbits per bin 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 5000 6000 7000 8000 Log(10) P Teff [K]
Van Eylen, Winn & Albrecht 2016, ApJ Winn et al. 2010, Albrecht et al. 2012 Hot (radiative) stars are slow to circularize (binary) or align (planets).
Limitation: evolutionary state of stars? Awaiting PLATO... Few short-period planets orbit evolved stars e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015 Few short-period planets orbit evolved stars e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
1 Tidal destruction: As stars evolve, short-period planets are destroyed. e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013 Few short-period planets orbit evolved stars e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
1 Tidal destruction: As stars evolve, short-period planets are destroyed. e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013 Few short-period planets orbit evolved stars e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
1 Tidal destruction: As stars evolve, short-period planets are destroyed. e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013 2 Planet formation: mass shortens lifetime protoplanetary disk e.g. Burkert & Ida 2007, Kretke et al. 2009, Currie 2009 Few short-period planets orbit evolved stars e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
1 Tidal destruction: As stars evolve, short-period planets are destroyed. e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013 2 Planet formation: mass shortens lifetime protoplanetary disk e.g. Burkert & Ida 2007, Kretke et al. 2009, Currie 2009 Few short-period planets orbit evolved stars e.g. Bowler et al. 2010, Johnson et al. 2010, Reffert et al. 2015
1 Tidal destruction: As stars evolve, short-period planets are destroyed. e.g. Rasio et al. 1996, Villaver & Livio 2009, Schlaufman & Winn 2013 2 Planet formation: mass shortens lifetime protoplanetary disk e.g. Burkert & Ida 2007, Kretke et al. 2009, Currie 2009
Spectroscopic mass? ⇒ asteroseismology! see e.g. Hjørringgaard et al. 2017, Stello et al. 2017 40 ) −1 20
0
−20 HARPS
radial velocity (m s FIES −40 PFS
−0.05 1.05
) 30 −1 20 10 0 −10 −20 O − C (m s −30 0.0 0.2 0.4 0.6 0.8 1.0 orbital phase
Van Eylen et al. 2016b, 2016 c
See also KESPRINT talk by Csizmadia!
K2-39: evolved subgiant with 4.6 day period planet?!
1.0005
1.0000 relative flux 0.9995
−0.154 0.154 0.0004 0.0002 0.0000
O − C −0.0002 −0.0004
−0.154 0.154 −15 −10 −5 0 5 10 15 time (hr) K2-39: evolved subgiant with 4.6 day period planet?!
40 1.0005 ) −1 20
1.0000 0
relative flux −20 HARPS 0.9995
radial velocity (m s FIES −40 PFS
−0.05 1.05
) 30
−0.154 0.154 0.0004 −1 20 0.0002 10 0.0000 0 −10 O − C −0.0002 −20
−0.0004 O − C (m s
−0.154 0.154 −30 −15 −10 −5 0 5 10 15 0.0 0.2 0.4 0.6 0.8 1.0 time (hr) orbital phase
Van Eylen et al. 2016b, 2016 c
See also KESPRINT talk by Csizmadia! If tides destroy planets around evolved stars: closest-in planets least likely to exist/survive K2-39b: t ≈ 10, 000 yr Period decay: P˙ ≈ 40 sec/yr (Currently: P˙ < 37 min/yr)
Waiting for PLATO to revisit systems... Waiting for PLATO to detect period decay...
0.5
0.4
0.3 Kep-432b [AU]
a 0.2 K2-99b Kep-56c Kep-56b 0.1 K2-97b Kep-91b K2-39b 0 1 2 3 4 5 6 7 8 R? [R ]
Van Eylen et al. 2016c Waiting for PLATO to revisit systems... Waiting for PLATO to detect period decay...
0.5
0.4
0.3 Kep-432b [AU]
a 0.2 K2-99b Kep-56c Kep-56b 0.1 K2-97b Kep-91b K2-39b 0 1 2 3 4 5 6 7 8 R? [R ]
Van Eylen et al. 2016c If tides destroy planets around evolved stars: closest-in planets least likely to exist/survive K2-39b: t ≈ 10, 000 yr Period decay: P˙ ≈ 40 sec/yr (Currently: P˙ < 37 min/yr) 0.5
0.4
0.3 Kep-432b [AU]
a 0.2 K2-99b Kep-56c Kep-56b 0.1 K2-97b Kep-91b K2-39b 0 1 2 3 4 5 6 7 8 R? [R ]
Van Eylen et al. 2016c If tides destroy planets around evolved stars: closest-in planets least likely to exist/survive K2-39b: t ≈ 10, 000 yr Period decay: P˙ ≈ 40 sec/yr (Currently: P˙ < 37 min/yr)
Waiting for PLATO to revisit systems... Waiting for PLATO to detect period decay... PLATO Science Goals sci.esa.int/plato/42277-science
Asteroseismology-planet results from Kepler/K2:
1 Uniqueness of our Solar System: eccentricities, obliquities, multi-planets e.g. Huber et al. 2013, Van Eylen et al. 2014, Lund et al. 2014, Van Eylen & Albrecht 2015, Campante et al. 2016
2 Interiors of Terrestrial and Gas Planets: radius gap e.g. Lundkvist et al. 2016, Fulton et al. 2017, Van Eylen, Agentoft et al. submitted
3 Evolution of Planetary Systems: planets on sub(giants), white dwarfs e.g. Grunblatt et al. 2016, Van Eylen et al. 2016b, 2016c, van Sluijs & Van Eylen 2017 (in prep.)
4 Planetary Atmospheres and Star-Planet Interactions: tidal alignment, orbit decay, binary stars e.g. Lillo-Box et al. 2014, Van Eylen et al. 2016a (binary stars!) , Van Eylen et al. 2016c
5 Structure and Evolution of the Milky Way: galactic archaeology e.g. Miglio et al. 2013, Casagrande et al. 2014, Stello et al. 2017, Silva Aguirre et al. 2017
We will do order(s) of magnitude better with PLATO! Extra slides Photo-evaporation of close-in planets?
Lundkvist et al. 2016 Photo-evaporation of close-in planets?
Fulton et al. 2017 Photo-evaporation of close-in planets?
18 16 14 12 10 8 # Stars 6 4 2 0 0.7 1.0 1.3 1.8 2.4 3.5 4.5 6.0 8.0 12.0 20.0 Radius [R ] ⊕
Van Eylen, Agentoft, Lundkvist et al. 2017, submitted Photo-evaporation of close-in planets?
Fulton et al. 2017 Photo-evaporation of close-in planets?
4.0
3.5
3.0 ] ⊕
R 2.5 [
R 2.0
1.5
1.0 3000 1000 300 100 30 10 Stellar light relative to Earth
Van Eylen, Agentoft, Lundkvist et al. 2017, submitted IF 1 = 2: eccentric orbit 6 ρ?,transit = ρ?,seismo eccentricity, BUT: 6 ⇒ 1 angle of periastrion ω? 2 impact parameter b? 3 transit timing variations? 4 false positives, ...?
See e.g.: Seager and Mallen-Orn´elas2003, Ford et al. 2008, Dawson & Johnson 2012, Kane et al. 2012, Kipping 2014, Plavchan et al. 2014, Price et al. 2015, Van Eylen & Albrecht 2015
Eccentricity of planets without RV
1. ρ? from transit duration (T ) 2. ρ? from asteroseismology (assuming a circular orbit) Directly from large frequency 1 T R?/a: separation: ∆ν √ρ? ∝ ∝ 2 R?/a ρ? (from Kepler’s law): Easiest to determine! ∝ Eccentricity of planets without RV
1. ρ? from transit duration (T ) 2. ρ? from asteroseismology (assuming a circular orbit) Directly from large frequency 1 T R?/a: separation: ∆ν √ρ? ∝ ∝ 2 R?/a ρ? (from Kepler’s law): Easiest to determine! ∝
IF 1 = 2: eccentric orbit 6 ρ?,transit = ρ?,seismo eccentricity, BUT: 6 ⇒ 1 angle of periastrion ω? 2 impact parameter b? 3 transit timing variations? 4 false positives, ...?
See e.g.: Seager and Mallen-Orn´elas2003, Ford et al. 2008, Dawson & Johnson 2012, Kane et al. 2012, Kipping 2014, Plavchan et al. 2014, Price et al. 2015, Van Eylen & Albrecht 2015 2 3/2 ρ? (1−e ) Observable: transit duration or density ratio = 3 ρ?,transit (1+e sin ω) Angle ω is unknown. ... but often also affects the shape.
Eccentricity does not.
Changing the impact parameter can also change the duration... Eccentricity does not.
Changing the impact parameter can also change the duration...
... but often also affects the shape. Changing the impact parameter can also change the duration...
... but often also affects the shape.
Eccentricity does not. Sum: Sum:
And transit timing variations (TTV) can complicate this: No TTV TTV Sum: Sum:
And transit timing variations (TTV) can complicate this: No TTV TTV Sum: Sum:
And transit timing variations (TTV) can complicate this: No TTV TTV And transit timing variations (TTV) can complicate this: No TTV TTV
Sum: Sum: Some ‘singles’ have TTVs or RV companions.
1.0 TTV RV observations RV companion 0.8
0.6
0.4 Eccentricity 0.2
0.0 101 102 103 Period [d]
Van Eylen et al. 2017, in prep. Half have companion stars, but no clear trend.
Close Companion Star Single Star 1.0
0.8
0.6
0.4 Eccentricity 0.2
0.0 4900 5300 5700 6100 6500 Teff [K]
Companion data from Furlan et al. 2017; Van Eylen et al. 2017, in prep.
See Mann et al. 2017, binary stars higher eccentricity? A few singles have inclination measurements + eccentricity.
0.9 0.8 0.7 0.6 0.5 0.4 0.3 Eccentricity 0.2 0.1 0.0 0 15 30 45 60 75 90 Stellar Inclination [deg]
Van Eylen et al. 2017, in prep., with obliquities from Hirano et al. 2012, 2014 Morton et al. 2014, Van Eylen et al. 2014, Quinn et al. 2015, Campante et al. 2016 Temperature detection bias?
102 Period
101
4900 5300 5700 6100 6500 Teff [K] Temperature detection bias?
6
5
4 ] ⊕ R
[ 3
p
R 2
1
0 4900 5300 5700 6100 6500 Teff [K]