TY - JOUR
T1 - Spin-orbit measurements and refined parameters for the exoplanet systems WASP-22 and WASP-26
AU - Anderson, D.~R.
AU - Collier Cameron, A.
AU - Gillon, M.
AU - Hellier, C.
AU - Jehin, E.
AU - Lendl, M.
AU - Queloz, D.
AU - Smalley, B.
AU - Triaud, A.~H.~M.~J.
AU - Vanhuysse, M.
PY - 2011/10/1
Y1 - 2011/10/1
N2 - We report on spectroscopic and photometric observations through transits of the exoplanets WASP-22b and WASP-26b, intended to determine the systems' spin-orbit angles. We combine these data with existing data to refine the system parameters. We measure a sky-projected spin-orbit angle of 22 plusmn 16deg for WASP-22b, showing the planet's orbit to be prograde and, perhaps, slightly misaligned. We do not detect the Rossiter-McLaughlin effect of WASP-26b due to its low amplitude and observation noise. We place 3-$ upper limits on orbital eccentricity of 0.063 for WASP-22b and 0.050 for WASP-26b. After refining the drift in the systemic velocity of WASP-22 found by Maxted et al. (2010, AJ, 140, 2007), we find the third body in the system to have a minimum-mass of 5.3 plusmn 0.3 M$_Jup$ (a$_3$ / 5 AU)$^2$, where a$_3$ is the orbital distance of the third body. Based on observations made with the HARPS spectrograph on the 3.6-m ESO telescope (proposal 085.C-0393), the 0.6-m Belgian TRAPPIST telescope, and the CORALIE spectrograph and the Euler camera on the 1.2-m Euler Swiss telescope, all at the ESO La Silla Observatory, Chile.The photometric time-series and radial velocity data used in this work are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/534/A16
AB - We report on spectroscopic and photometric observations through transits of the exoplanets WASP-22b and WASP-26b, intended to determine the systems' spin-orbit angles. We combine these data with existing data to refine the system parameters. We measure a sky-projected spin-orbit angle of 22 plusmn 16deg for WASP-22b, showing the planet's orbit to be prograde and, perhaps, slightly misaligned. We do not detect the Rossiter-McLaughlin effect of WASP-26b due to its low amplitude and observation noise. We place 3-$ upper limits on orbital eccentricity of 0.063 for WASP-22b and 0.050 for WASP-26b. After refining the drift in the systemic velocity of WASP-22 found by Maxted et al. (2010, AJ, 140, 2007), we find the third body in the system to have a minimum-mass of 5.3 plusmn 0.3 M$_Jup$ (a$_3$ / 5 AU)$^2$, where a$_3$ is the orbital distance of the third body. Based on observations made with the HARPS spectrograph on the 3.6-m ESO telescope (proposal 085.C-0393), the 0.6-m Belgian TRAPPIST telescope, and the CORALIE spectrograph and the Euler camera on the 1.2-m Euler Swiss telescope, all at the ESO La Silla Observatory, Chile.The photometric time-series and radial velocity data used in this work are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/534/A16
KW - binaries: eclipsing, planetary systems, stars: individual: WASP-22, stars: individual: WASP-26
U2 - 10.1051/0004-6361/201117597
DO - 10.1051/0004-6361/201117597
M3 - Article
SN - 0004-6361
VL - 534
SP - A16
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
ER -