The obliquities of the planetary systems detected with CHEOPS. Guillaume Hébrard Institut d astrophysique de Paris Observatoire de Haute-Provence

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1 The obliquities of the planetary systems detected with CHEOPS Guillaume Hébrard Institut d astrophysique de Paris Observatoire de Haute-Provence CHEOPS Characterizing Exoplanets Satellite Science Workshop #3, Madrid, Spain, June 18, 2015

2 Rossiter-McLaughlin effect (1924) (see also Holt 1893) (Gaudi & Winn 2007)

3 HD b SOPHIE OHP Residual of the Keplerian model Amplitude of the RM anomaly: f (R p /R, v sin i, b)

4 λ = 0 λ = 30 λ = 60 Gaudi & Winn (2007)

5 TrES-2 (Winn et al. 2008a) TrES-1 (Narita et al. 2007) HD b (Winn et al. 2007) CoRoT-2b (Bouchy et al. 2008) HAT-P-1b (Johnson et al. 2008) 2008: ~ 10 observed spectroscopic transits over ~ 50 known transiting planets All well aligned and prograde WASP-14b (Joshi et al. 2008) Validation of planetary formation and evolution models where a single giant planet HD b migrates (Queloz et al. 2000) in a proto-planetary disk HD b (Loeillet et al. 2007) (perpendicular to the stellar spin axis) HD b (Winn et al. 2006) HD b (Winn et al. 2005) HD b (Wolf et al. 2007)

6 2008: First case of spin-orbit misalignment XO-3 v sin i = 18.5 km/s M p = 12.5 M Jup P = 3.2 d e = 0.3 λ = 70 ± 15 SOPHIE λ = /- 3.7 (Winn et al. 2009; Hirano et al. 2011) Keck Hébrard et al. (2008)

7 2009: Second case of spin-orbit misalignment HD M p = 4.1 M jup P = d e = 0.93 Radial velocity (km/s) Relative flux (MEarth) Photometry (OHP 120) Spectroscopy (OHP SOPHIE) (MEarth) 13 Feb (0h) 13 Feb (12h) 14 Feb (0h) Moutou et al. (2009)

8 HAT-P-7 (Winn et al. 2009) λ = /- 9.4 WASP-17 (Triaud et al. 2010) λ = /- 4.7 WASP-8 (Queloz et al. 2010) λ = /- 3.9 HAT-P-6 (Hébrard et al. 2011) λ = 166 +/- 10

9 Obliquity measurements From Rossiter effect; Or from alternative, emerging methods: Tomography; Stroboscopic starspots; Stellar inclination.

10 Obliquity measurements from tomography KOI-12b P = 17.86d R = 1.4 R Jup M < 10 M Jup λ = 16 ± 20 Bourrier et al. (2015) λ = 12.6 ± 3.0

11 Today: ~ 100 measured obliquities Triaud (2011) 30 misaligned systems, including 11 retrograde, 5 nearly polar Albrecht et al. (2012) Hébrard et al. (2011) Winn et al. (2010) Planetary mass (M Jup )

12 Why the obliquity of planetary orbit could change? KT: Kozai mechanism with Tidal circularization (Fabrycky & Tremaine 2007) 45% to 85% of hot jupiters are misaligned (Triaud et al. 2010): Most hot jupiters are formed from KT rather than migration in disk SKT: planet Scattering, Kozai mechanism, and Tidal circularization (Nagasawa et al. 2008) 2 modes (Morton & Johnson 2011): a part of planets migrated through disk migration (that preserve spin-orbit alignment) and another part (34% to 76%) migrated through SKT. Or, why the inclination of the star could change? early on through magnetosphere-disk interactions (Lai et al. 2010) later through elliptical tidal instability (Cébron et al. 2012)

13 Currently, hot jupiters are the main targets for available Rossiter measurements: Hot jupiters represent the majority of known planets transiting bright stars; Lack of transiting planets on long periods around bright stars; Lack of non-giant transiting planets around bright stars; Lack of multiple transiting systems around bright stars.

14 CHEOPS: exploring the obliquity in multiple systems, as well as low-mass and long-period planets.

15 Where CHEOPS planets could add pertinent obliquity measurements? λ [Degrees] CHEOPS

16 Where CHEOPS planets could add pertinent obliquity measurements? Obliquities of lowmass and smallradius planets remain largely unexplored. λ [Degrees] CHEOPS λ [Degrees]

17 HD b λ = 42 +/- 8 Orbital period: 111 days Transit duration: hours SOPHIE Jan 2010 Hébrard et al. (2010) Keck Jun 2009 Winn et al. (2009) SOPHIE Feb 2009 Moutou et al. (2009) Spitzer Hébrard et al. (2010)

18 Non-giant planets GJ 436 b Lanotte et al. (2014) Small planetary radius: Low-amplitude RM effect P = 2.64 d M p = 25 M earth R p = 4.1 R Earth v sin i = km/s RM anomaly amplitude < 2 m/s

19 Non-giant planets HAT-P-11 b Keck Winn et al. (2010) Small planetary radius: Low-amplitude RM effect +26 λ = P = d M p = 26 M earth R p = 4.7 R Earth v sin i = 1.0 km/s RM anomaly amplitude: 1.5 m/s

20 Non-giant planets 55 Cnc e HARPS-N Bourrier & Hébrard (2014) +13 λ = Small planetary radius: Low-amplitude RM effect P = d M p = 7.99 M earth R p = 1.99 R Earth v sin i = 2.4 km/s RM anomaly amplitude: 0.6 m/s López-Morales et al. (2014) RM anomaly amplitude < 0.35 m/s HARPS+HARPS-N

21 Low-mass planets Kepler-11 Masses = [ ] M Earth Radii = [ ] R Earth Planet Transit duration RM amplitude for vsini=0.5km/s RM amplitude for vsini=4.0km/s Keplerian amplitude K Orbital period (hours) (m/s) (m/s) (m/s) (days) Kepler-11b Kepler-11c Kepler-11d Kepler-11e Kepler-11f Kepler-11g CHEOPS-??

22 Conclusions Obliquities constrain planetary formation and evolution models. Obliquities could be measured in spectroscopy through the Rossiter-McLaughlin anomaly (other methods are emerging). Available observations on hot jupiters jeopardizes disk migration as the standard/unique model explaining their origin. Obliquities measurements on CHEOPS planets will allow such studies to be extended on low-mass and long-period planets, and multiple-planets systems. It will require high-precision spectroscopic observations.