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Stellar obliquities in exoplanetary systems
Josh Winn
Simon Albrecht, Roberto Sanchis-Ojeda, Teruyuki HiranoAndrew Howard, John Johnson, Geoff MarcyBill Cochran, Dan Fabrycky, the Kepler team
Massachusetts Institute of Technology
obliquity (n.)1 : deviation from parallelism2 : a deviation from moral rectitude or sound thinking
Semimajor axis [AU]
Ecce
ntric
ity
Jupiter
Semimajor axis [AU]
Ecce
ntric
ity
Disk-planet interactionsLow
obliquity
Semimajor axis [AU]
Ecce
ntric
ity
Disk-planet interactions
Few-body dynamics
Tida
l dis
sipa
tion
High obliquity
Low obliquit
y
The Sanchis–Nutzman effect
l = 0°
l = 0°
l = 0°
l = 0°
l = 0°
l = 0°
l = 0° l = 100°
l = 0° l = 100°
l = 0° l = 100°
l = 0° l = 100°
l = 0° l = 100°
…
l = 0° l = 100°
…
l = 0° l = 100°
…
l = 0° l = 100°
The starspot-anomaly pattern reveals the stellar obliquity
…
Sanchis-Ojeda et al. (2011 a,b)Nutzman, Fabrycky, & Fortney (2011)
Nutzman, Fabrycky, & Fortney (2011)
Corot-2
Nutzman, Fabrycky, & Fortney (2011) — see also Désert et al. (2011)
Observed
Calculated (l = 0°) l = 5 ± 12°
Corot-2
Sanchis-Ojeda & Winn (2011)
HAT-P-11
Sanchis-Ojeda & Winn (2011)
Time from midtransit [days]
Sanchis-Ojeda & Winn (2011)
Sanchis-Ojeda & Winn (2011)
Christoph Scheiner (1573-1650)
Flux
Time
The Rossiter-McLaughlin effect
Doppler shift
Time
The Rossiter-McLaughlin effect
Doppler shift
Time
The Rossiter-McLaughlin effect
Doppler shift
Time
The Rossiter-McLaughlin effect
Doppler shift
Time
The Rossiter-McLaughlin effect
Doppler shift
Time
The Rossiter-McLaughlin effect
Queloz et al. (2000); Ohta, Taruya, & Suto (2005); Gaudi & Winn (2007)
Measuring the projected obliquity
l = –1.4° ± 1.1°Winn et al. (2006);see also Triaud et al. (2009)
Low obliquity
HD 189733
XO-3
l = 37.3° ± 3.0°Hirano et al. (2011);see also Hébrard et al. (2008), Winn et al. (2009)
Moderate obliquity
Winn et al. (2009)
High obliquity (retrograde)
Narita et al. (2009)
Triaud et al. (2010)
Valenti & Fischer (2005)
Pinsonneault et al. (2001)
(Zahn 1977)
Problem: Orbit decays on same timescale as realignment
Solution: Realign only the convective zone?
Reality
Constant-Q model
Different Q’s for realignment and orbital decay(D. Lai, in preparation)
KOI-631.0 M , 1.0 R
P = 9.4 daysRp = 6.5 R
Prot = 5.4 days≈ (4/7) Porb
KOI-63
Current obliquity measurements
Current obliquity measurements
Kepler candidates
Current obliquity measurements
Kepler candidates
Kepler multi-planet candidates
Starspot anomalies
Rossiter-McLaughlin effect
Rotation-rate statistics (Schlaufman 2010)
Gravity darkening (Barnes 2010, Szabo et al. 2011)
Rotational Doppler boosting (van Kerkwijk et al. 2010)
Spin precession TDVs (Damiani & Lanza 2011)
Current obliquity measurements
Kepler candidates
Kepler multi-planet candidates
