Observatoire Astronomique de l’Université de Genève,
Chemin des Maillettes 51,
2 Astrophysics Group, Keele University, Staffordshire, ST55 BG, UK
3 SUPA, School of Physics & Astronomy, University of St. Andrews, North Haugh, KY16 9SS, St. Andrews, Fife, Scotland, UK
4 Institut d’Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août, 17, Bat. B5C, Liège 1, Belgium
5 Department of Physics, University of Warwick, Coventry CV4 7AL, UK
6 N. Copernicus Astronomical Centre, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland
7 Department of Physics and Astronomy, University of Leicester, Leicester, LE17 RH, UK
Received: 13 December 2012
Accepted: 9 January 2013
We report the discovery of a planet transiting the star WASP-80 (1SWASP J201240.26-020838.2; 2MASS J20124017-0208391; TYC 5165-481-1; BPM 80815; V = 11.9, K = 8.4). Our analysis shows this is a 0.55 ± 0.04 Mjup, 0.95 ± 0.03 Rjup gas giant on a circular 3.07 day orbit around a star with a spectral type between K7V and M0V. This system produces one of the largest transit depths so far reported, making it a worthwhile target for transmission spectroscopy. We find a large discrepancy between the vsini⋆ inferred from stellar line broadening and the observed amplitude of the Rossiter-McLaughlin effect. This can be understood either by an orbital plane nearly perpendicular to the stellar spin or by an additional, unaccounted for source of broadening.
Key words: planetary systems / binaries: eclipsing / stars: individual: WASP-80 / techniques: radial velocities / techniques: photometric / techniques: spectroscopic
Using WASP-South photometric observations, from Sutherland (South Africa), confirmed with the 60 cm TRAPPIST robotic telescope, EulerCam, and the CORALIE spectrograph on the Swiss 1.2 m Euler Telescope, and HARPS on the ESO 3.6 m (Prog ID 089.C-0151), all three located at La Silla Observatory, Chile.
Radial velocity and photometric data are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(188.8.131.52) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/551/A80
© ESO, 2013