K2-31b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright G7V star

S. Grziwa; D. Gandolfi; Sz. Csizmadia; M. Fridlund; H. Parviainen; H. J. Deeg; J. Cabrera; A. A. Djupvik; S. Albrecht; E. B. Palle; M. Pätzold; V. J. S. Béjar; J. P. Arranz; P. Eigmüller; A. Erikson; J. P. U. Fynbo; E. W. Guenther; A. P. Hatzes; A. Kiilerich; J. Korth; T. Kuutma; P. Montanés-Rodríguez; D. Nespral; G. Nowak; H. Rauer; J. Saario; D. Sebastian; D. Slumstrup

doi:10.3847/0004-6256/152/5/132

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arXiv · 1510.09149

K2-31b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright G7V star

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Abstract

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 an 1.26-day-orbit around a G7\,V star ($M_\star=0.91$~\Msun, $R_\star=0.78$~\Rsun). The planetary radius is poorly constrained (0.7$<$$R_\mathrm{p}$$<$1.4~\Rjup), owing to the grazing transit and the low sampling rate of the K2 photometry.

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S. Grziwa, D. Gandolfi, Sz. Csizmadia, M. Fridlund, H. Parviainen, H. J. Deeg, J. Cabrera, A. A. Djupvik, S. Albrecht, E. B. Palle, M. Pätzold, V. J. S. Béjar, J. P. Arranz, P. Eigmüller, A. Erikson, J. P. U. Fynbo, E. W. Guenther, A. P. Hatzes, A. Kiilerich, J. Korth, T. Kuutma, P. Montanés-Rodríguez, D. Nespral, G. Nowak, H. Rauer, J. Saario, D. Sebastian, D. Slumstrup. 2016-08-30. K2-31b, a grazing transiting hot Jupiter on an 1.26-day orbit around a bright G7V star. https://doi.org/10.3847/0004-6256%2F152%2F5%2F132

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