1. Asteroseismology of Kepler
Exoplanet Host Stars
Travis Metcalfe (SSI)

2. 1992: first pulsar planets 3 planet system 2 = 4 x Earth mass
1 = 2 x Moon mass
Orbits closer than Mercury

3. 1995: first radial velocity planet
0.5 x Jupiter mass
Orbit closer than Mercury

4. 2001: first transiting planet
Orbit closer than Mercury
Size near Jupiter

5. Exoplanet atmospheres
Detections
- Sodium
- Carbon monoxide
- Water vapour

6. 2004: first microlensing planet
Hosted by a tiny red dwarf
Orbit size similar to Mars
Mass similar to Jupiter

7. 2008: first direct image Mass = 3 x Jupiter Orbit size = 3 x Neptune
Host star mass = 2 x Sun

8. 2010: first habitable planet?
Gliese 581g
Mass = 3 x Earth
Orbit size = 0.4 x Mercury
Host star mass = 0.3 x Sun

12. Higher temperature = faster sound speed
Lighter gases = faster sound speed
He demonstration
SF6 demonstration

13. He demonstration
SF6 demonstration

14. Global oscillation properties
nmax
Elsworth & Thompson (2004)

15. Scaling relations
Mathur et al. (2012)

16. Grid-based methods
Mathur et al. (2012)

17. Fitting the frequencies
Metcalfe et al. (2012)

18. Asteroseismic Modeling Portal
Chaplin et al. (2011, Science)
Stellar evolution tracks from ASTEC, pulsation analysis with ADIPLS
Parallel genetic algorithm optimizes globally, local analysis + SVD for errors
Stellar age from match to large separation, correct surface effects empirically
< M <
< Z <
< Y <
< a < 3.0
Metcalfe et al. (2009), Woitaszek et al. (2009)

19. Kepler-21: a love story
1.64±0.04 Re planet in a 2.8-day orbit around an oscillating F subgiant
Asteroseismic target prior to exoplanet discovery, expanded collaboration
radius (1.86±0.04 R), mass (1.34±0.06 M), age (2.84±0.34 Gyr)
Howell et al. (2012)

20. Kepler-22: habitable super-Earth
2.38±0.13 Re planet with 290-d orbit in habitable zone of G5 host star
Spectroscopy and global oscillation properties for grid-based modeling
radius (0.98±0.02 R), mass (0.97±0.06 M), age (~4 Gyr?)
Borucki et al. (2012)

21. Kepler-36: formation puzzle
Carter et al. (2012, Science)

22. Kepler-36: formation puzzle
1.5 and 3.7 Re planets in 13.8-d and 16.2-d orbits (7:6 period ratio)
Asteroseismology and transit timing variations yield planet densities
Super-Earth and Neptune (8:1 density ratio) in neighboring orbits. How?
Carter et al. (2012, Science)

23. Kepler-##: smallest exoplanet
0.28 / 0.8 / 2.1 Re planets in 13 / 21 / 39 day orbits (no TTVs yet detected)
radius (0.77±0.02 R), mass (0.80±0.04 M), age (~6 Gyr)
Innermost planet is smaller than Mercury (similar to size of Moon)
Barclay et al. (submitted)

24. Future prospects
Longer data sets will resolve mode splitting, providing independent constraints on rotational inclination and spin-orbit alignment.
Extended time series will probe variations due to magnetic cycles, and provide statistics on stellar super-flares (with implications for habitability).
Comparison with control sample of stars without known planets may reveal correlations between stellar composition and occurrence of planets.