EPIC 204129699b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright solar like star

Grziwa, S.; Gandolfi, D.; Csizmadia, Sz.; Fridlund, M.; Parviainen, H.; Deeg, H. J.; Cabrera, J.; Djupvik, A. A.; Albrecht, S.; Palle, E. B.; Pätzold, M.; Béjar, V. J. S.; Arranz, J. P.; Eigmüller, P.; Erikson, A.; Fynbo, J. P. U.; Guenther, E. W.; Hatzes, A. P.; Kiilerich, A.; Korth, J.; Kuutma, T.; Montanés-Rodríguez, P.; Nespral, D.; Nowak, G.; Rauer, H.; Saario, J.; Sebastian, D.; Slumstrup, D.
The Astronomical Journal, Volume 152, Issue 5, article id. 132, 5 pp. (2016).


We report the discovery of K2-31b, the first confirmed transiting hot Jupiter detected by the K2 space mission. We combined K2 photometry with FastCam lucky imaging and FIES and HARPS high-resolution spectroscopy to confirm the planetary nature of the transiting object and derived the system parameters. K2-31b is a 1.8-Jupiter-mass planet on a 1.26-day orbit around a G7 V star ({M}\star =0.91 M , {R}\star =0.78 R ). The planetary radius is poorly constrained (0.7 < R p < 1.4 R Jup),15 owing to the grazing transit and the low sampling rate of the K2 photometry.16