TY - JOUR
T1 - Measurement of the spin-orbit angle of exoplanet HAT-P-1b
AU - Johnson, John Asher
AU - Winn, Joshua N.
AU - Narita, Norio
AU - Enya, Keigo
AU - Williams, Peter K.G.
AU - Marcy, Geoffrey W.
AU - Sato, Bun'ei
AU - Ohta, Yasuhiro
AU - Taruya, Atsushi
AU - Suto, Yasushi
AU - Turner, Edwin L.
AU - Bakos, Gaspar
AU - Paul Butler, R.
AU - Vogt, Steven S.
AU - Aoki, Wako
AU - Tamura, Motohide
AU - Yamada, Toru
AU - Yoshii, Yuzuru
AU - Hidas, Marton
PY - 2008/10/10
Y1 - 2008/10/10
N2 - We present new spectroscopic and photometric observations of the HAT-P-1 planetary system. Spectra obtained during three transits exhibit the Rossiter-McLaughlin effect, allowing us to measure the angle between the sky projections of the stellar spin axis and orbit normal, λ = 3.7° ±2.1°. The small value of λ for this and other systems suggests that the dominant planet migration mechanism preserves spin-orbit alignment. Using two new transit light curves, we refine the transit ephemeris and reduce the uncertainty in the orbital period by an order of magnitude. We find a upper limit on the orbital eccentricity of 0.067, with 99% confidence, by combining our new radial velocity measurements with those obtained previously.
AB - We present new spectroscopic and photometric observations of the HAT-P-1 planetary system. Spectra obtained during three transits exhibit the Rossiter-McLaughlin effect, allowing us to measure the angle between the sky projections of the stellar spin axis and orbit normal, λ = 3.7° ±2.1°. The small value of λ for this and other systems suggests that the dominant planet migration mechanism preserves spin-orbit alignment. Using two new transit light curves, we refine the transit ephemeris and reduce the uncertainty in the orbital period by an order of magnitude. We find a upper limit on the orbital eccentricity of 0.067, with 99% confidence, by combining our new radial velocity measurements with those obtained previously.
KW - Planetary systems: formation
KW - Stars: individual (ADS 16402a, HAT-P-1)
KW - Techniques: radial velocities
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U2 - 10.1086/591078
DO - 10.1086/591078
M3 - Article
AN - SCOPUS:53849110656
SN - 0004-637X
VL - 686
SP - 649
EP - 657
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -