Asteroseismology of Exoplanet Host Stars

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1 Asteroseismology of Exoplanet Host Stars Daniel Huber Institute for Astronomy, University of Hawaii Know Thy Star, Know Thy Planet October 2017

2 Crash Course in Asteroseismology for more details: Aerts, Christensen-Dalsgaard & Kurtz (2011, Springer) Basu & Chaplin (2017, Princeton)

3 SPB Cep δsct Giants roap Stochastic Coherent ( Classical ) Pulsators Dwarfs Sun ( Solar-like ) Oscillators

4 The Sun

5 δν dcs/dr (Age & interior structure) δν sound speed cs Δν = (2 dr/cs) -1 (M/R 3 ) 1/2 Ulrich (1986)

6 Δν = (2 dr/cs) -1 (M/R 3 ) 1/2 (density) The Sun Δν Teff + Δν, νmax Brown et al. (1991) νmax R <~ 5% M <~ 10% νmax νac M R -2 Teff 0.5 (gravity)

7 Asteroseismology & Exoplanets I: Precise Planet Properties

8 Kepler-36 Carter et al M & R + (RP/R ) 2 RP (<5% uncertainty!)

9 The Seismic Host Star Sample pre-kepler Kepler Huber et al Lundkvist et al. 2016

10 The Seismic Host Star Sample pre-kepler Kepler Kepler-37 & Kepler-444 Huber et al Lundkvist et al. 2016

11 Kepler-37 Kepler-444 R = / R R = / R Barclay et al Campante et al ~ Moon-sized planet orbiting a late G dwarf 5 sub-earth sized planets orbiting a ~12 Gyr old K dwarf

12 The Seismic Host Star Sample pre-kepler Kepler Huber et al Lundkvist et al. 2016

13 The Seismic Host Star Sample KOI-4 pre-kepler Kepler

14 The Seismic Host Star Sample KOI-4 see poster by Ashley Chontos! Chontos et al., in prep

15 The Seismic Host Star Sample Ok for longcadence Short-cadence data needed!

16 The Seismic Host Star Sample K2 Giants Orbiting Giants Survey Short-cadence data needed!

17 K2-97: K2 s first seismic host star Transits Keck/HIRES Asteroseismology R = 4.2 R P = 8.4 days RP = 1.31 RJ MP = 0.48 MJ Grunblatt et al. 2016

18 K2 Red Giant Planet Twins! Transits Keck/HIRES Asteroseismology R = 4.2 R P = 8.4 days RP = 1.31 RJ MP = 0.48 MJ R = 3.8 R P = 9.2 days RP = 1.30 RJ MP = 0.49 MJ Grunblatt et al. 2016, 2017

19 (Re-)inflated Giants Orbiting Giants Observational evidence for direct heating as the cause for planet inflation (Lopez & Fortney 2016) Grunblatt et al. (2016, 2017)

20 Asteroseismology & Exoplanets I: Dynamical Architectures of Planetary Systems

21 Gizon & Solanki (2003) Andrea Miglio University of Birmingham, UK

22 Hot Jupiters No Hot Jupiters Albrecht et al. (2013) easy to re-align hard to re-align Do Hot Jupiters form differently than other systems?

23 Hot Jupiters No Hot Jupiters seismic measurements! Kepler- 432 Kepler-50 & 65 Chaplin et al. (2013) Van Eylen et al. (2014) Quinn et al. (2015) Campante et al. (2016) Kepler-410 Albrecht et al. (2013) easy to re-align hard to re-align Do Hot Jupiters form differently than other systems?

24 Hot Jupiters Multiplanet Systems Kepler-56 Kepler- 432 Huber et al. (2013) Albrecht et al. (2013) easy to re-align hard to re-align Do Hot Jupiters form differently than other systems?

25 Hot Jupiters Multiplanet Systems Kepler-56 Kepler- 432 Huber et al. (2013) Non-transiting companion in ~600 Albrecht et al. (2013) easy to re-align day orbit. Culprit for hard to re-align misalignment? Do Hot Jupiters form differently than multiplanet systems? Otor et al. (2016) Boue & Fabrycky (2014)

26 That s all great but how accurate is asteroseismology really?

27 Martig et al Fulton et al Brewer et al Bastien et al. 2013

28 CHARA Asteroseismology Program Asteroseismology Interferometry Metcalfe et al. (2015) White et al. (2013) Direct measurement of R through angular diameter + parallax. How does this compare with asteroseismic scaling relations?

29 Asteroseismology vs Interferometry Huber et al. (2012) White et al. (2013) White et al. in prep

30 Asteroseismology vs Interferometry Huber et al. (2012) evolutionary state dependent White et al. (2013) systematic at the ~few % level? White et al. in prep Huber et al. (2012) White et al. (2013) White et al. in prep White et al. in prep

31 Seismo vs Gaia Seismo vs CHARA Huber et al. (2017) White et al. in prep

32 Huber et al. (2017) Bottom Line: systematics at the <5% level in R (~ 0.03 dex in logg) between fundamental methods are not trivial

33 What will we learn from TESS?

34 TESS Asteroseismology ~5000 detections in dwarfs & subgiants (factor ~10 increase over Kepler)

35 TESS Asteroseismology ~5000 detections in dwarfs & subgiants (factor ~10 increase over Kepler) (for giants: ~1e6+ detections expected)

36 Seismic TESS Exoplanet Hosts Kepler (~100) TESS discoveries (~200) TESS known hosts (~100) Campante et al. (2016)

37 Seismic TESS Exoplanet Hosts How efficient is planet re-inflation? How rare is Kepler-56? Occurrence as a function of mass, evolutionary state? 51 Peg! Precise planet masses, radii & compositions

38 Conclusions Asteroseismology is a powerful tool to precisely characterize host stars and dynamical architectures of exoplanet systems Empirical validations of asteroseismic scaling relations (e.g. using interferometry) are promising, but beware of systematics at the few % level! TESS will continue Kepler s revolution of asteroseismology, increasing (mostly) the seismic subgiant sample by a factor of 10 (~1e6 giants!)

39 Better Stars, Better Planets: Exploiting the Stellar - Exoplanet Synergy (exostar19) April - June 2019 (Conference May ) KITP Santa Barbara Coordinators: Victor Silva Aguirre, Rebekah Dawson, Jim Fuller, Daniel Huber, Katja Poppenhaeger Science Advisors: Josh Winn & Eric Agol

40 Oscillation (& granulation) amplitudes are heavily biased towards evolved stars

41 seismic density lifts degeneracies to constrain eccentricities Sliski & Kipping 2015, Van Eylen & Albrecht 2015

42 Seismic Sample Small planets are preferentially on circular orbits important assumption e.g. for planet occurrence rates! Van Eylen & Albrecht 2015