ASTR 405: Exoplanetary Science. Stephen Kane

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1 ASTR 405: Exoplanetary Science Stephen Kane

2 Transiting planets discovered via radial velocity HD b HD b HD b GJ 436 b 55 Cancri e GJ 3470 b HD b (P = 21 days) HD b (P = 111 days) These tend to be the brightest of the known transiting planet host stars This has allowed further access to characterization (atmospheres) Transit method RV method

3 Laughlin et al., 2009, Nature, 457, 562

4 Orbital Geometry The transit probability for an eccentric orbit has the potential to be much higher than for circular orbits This can have an important effect for relatively long period planets The predicted time of mid-transit can be significantly incorrect! Kane & von Braun, 2008, ApJ, 689, 492 Kane & von Braun, 2009, PASP, 121, 1096

5 Orbital Geometry Kane & von Braun, 2008, ApJ, 689, 492 Kane & von Braun, 2009, PASP, 121, 1096

6 Application to Known Exoplanets Kane & von Braun, 2008, ApJ, 689, 492 Kane & von Braun, 2009, PASP, 121, 1096

7 Application to Known Exoplanets Kane & von Braun, 2008, ApJ, 689, 492 Kane & von Braun, 2009, PASP, 121, 1096

8 Application to Known Exoplanets Kane & von Braun, 2008, ApJ, 689, 492 Kane & von Braun, 2009, PASP, 121, 1096

9 Transit Ephemerides The quality of a transit window depends upon the uncertainties in the orbital fit parameters Kane et al., 2009, PASP, 121, 1386

10 Transit Ephemerides The large transit windows for longer period planets makes them unfeasible targets If the transit windows were sufficiently small, all of the transit windows could be covered with minimal telescope time Improvement of orbital parameters and optimal follow-up of new planets is needed Kane et al., 2009, PASP, 121, 138

11 Transit Ephemerides The large transit windows for longer period planets makes them unfeasible targets If the transit windows were sufficiently small, all of the transit windows could be covered with minimal telescope time Improvement of orbital parameters and optimal follow-up of new planets is needed Kane et al., 2009, PASP, 121, 138

12 Transit Ephemerides The quality of a transit window depends upon the uncertainties in the orbital fit parameters Kane et al., 2009, PASP, 121, 1386

13 The Need For TERMS Only a handful of additional RV measurements at carefully planned epochs can yield a significant improvement in orbital parameters These four measurements reduce the transit window from 82.3 days to 3.7 days... a factor of ~25! Fischer et al., 2007, ApJ, 669, 1336 Kane et al., 2009, PASP, 121, 1386

14 TERMS Telescopes CTIO 0.9m CTIO 1.0m LCO 1.0m LCOGT MOST Peter van de Kamp Observatory 0.6m APT (Fairborn Observatory) Keck/HIRES UCO/Lick 3.0m Hobby-Eberly Telescope HARPS CORALIE AAT Cross-matching with KELT targets Target selection for TESS & CHEOPS

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16 Kane et al., 2011, ApJ, 735, L41 19 years of Lick radial velocities

17 Kane et al., 2011, ApJ, 735, L years of APT photometry

18 HD b The orbital parameters resulting from the combined data yield an uncertainty in the transit mid-point of only 20 minutes! Kane et al. 2011, ApJ, 733, 28

19 HD b Kane et al. 2011, ApJ, 735, L41 Latham, D. 2012, NewAR, 56, 16 HD b Kane et al. 2011, ApJ, 737, 58 HD b Pilyavsky et al. 2011, ApJ, 743, 162

20 Each TERMS target results in... Greatly improved orbital parameters Refined transit ephemeris Ruling out or confirmation of transit Improved stellar properties Photometric stability of host star Constraints on additional companions

21 iota Draconis Kane et al., 2010, ApJ, 720, 1644

22 HD b

23 HD b

24 The HD System Wang et al. 2012, ApJ, 761, 46

25 The HD System Wang et al. 2012, ApJ, 761, 46

26 The HD System Wang et al. 2012, ApJ, 761, 46

27 The HD System Wang et al. 2012, ApJ, 761, 46

28 Kane & Raymond, 2014, ApJ, 784, 1

29 HD Hinkel et al., 2015, ApJ, in press

30 A Return to 70 Virginis Kane et al., 2015, ApJ, in press

31 Some Applications of Orbital Refinement Accurate ephemerides for planetary transit predictions, particularly for LONG PERIOD planets orbiting BRIGHT host stars Kane et al. 2011, ApJ, 733, 28 (HD b) Pilyavsky et al. 2011, ApJ, 743, 162 (HD b,c) Dragomir et al. 2012, ApJ, 754, 37 (HD b) Hinkel et al. 2015, ApJ, in press (HD b) Characterization studies of exoplanets during periastron passage Kane & Gelino 2010, ApJ, 724, 818 (Optical) Kane & Gelino 2011, ApJ, 741, 52 (Infra-red) Detection of additional planets in known systems Wang et al. 2012, ApJ, 761, 46 (HD b,c) Multi-planet phase variation studies Kane et al. 2011, ApJ, 740, 61 (55 Cancri) Kane & Gelino 2013, ApJ, 762, 129 (Kepler planets) Habitability of circumbinary planets Kane & Hinkel 2013, ApJ, 762, 7 Orbital dynamics and precession Kane et al. 2012, ApJ, 757, 105 Kane & Raymond 2014, ApJ, 784, 104

32 Transiting Exoplanet Survey Satellite (TESS) CHaracterising ExOPlanet Satellite (CHEOPS)