Bibcode
Crouzet, N.; McCullough, P. R.; Long, D.; Montañes Rodriguez, P.; Lecavelier des Etangs, A.; Ribas, I.; Bourrier, V.; Hébrard, G.; Vilardell, F.; Deleuil, M.; Herrero, E.; Garcia-Melendo, E.; Akhenak, L.; Foote, J.; Gary, B.; Benni, P.; Guillot, T.; Conjat, M.; Mékarnia, D.; Garlitz, J.; Burke, C. J.; Courcol, B.; Demangeon, O.
Referencia bibliográfica
The Astronomical Journal, Volume 153, Issue 3, article id. 94, 13 pp. (2017).
Fecha de publicación:
3
2017
Número de citas
38
Número de citas referidas
32
Descripción
Only a few hot Jupiters are known to orbit around fast rotating stars.
These exoplanets are harder to detect and characterize and may be less
common than around slow rotators. Here, we report the discovery of the
transiting hot Jupiter XO-6b, which orbits a bright, hot, and fast
rotating star: V = 10.25, T eff⋆ = 6720 ± 100 K,
v sin i ⋆ = 48 ± 3 km s‑1. We
detected the planet from its transits using the XO instruments and
conducted a follow-up campaign. Because of the fast stellar rotation,
radial velocities taken along the orbit do not yield the planet’s
mass with a high confidence level, but we secure a 3σ upper limit
M p < 4.4 M Jup. We also obtain
high-resolution spectroscopic observations of the transit with the
SOPHIE spectrograph at the 193-cm telescope of the Observatoire de
Haute-Provence and analyze the stellar lines profile by Doppler
tomography. The transit is clearly detected in the spectra. The radii
measured independently from the tomographic analysis and from the
photometric light curves are consistent, showing that the object
detected by both methods is the same and indeed transits in front of
XO-6. We find that XO-6b lies on a prograde and misaligned orbit with a
sky-projected obliquity {\boldsymbol{λ
}}=-20\buildrel{\circ}\over{.} 7+/- 2\buildrel{\circ}\over{.} 3. The
rotation period of the star is shorter than the orbital period of the
planet: P rot < 2.12 days, P orb = 3.77 days.
Thus, this system stands in a largely unexplored regime of dynamical
interactions between close-in giant planets and their host stars.