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arXiv · 1807.05865

K2-295 b and K2-237 b: two transiting hot Jupiters

A. M. S. Smith·Sz. Csizmadia·D. Gandolfi·S. Albrecht·R. Alonso·O. Barragán·J. Cabrera·W. D. Cochran·F. Dai·H. Deeg·Ph. Eigmüller·M. Endl·A. Erikson·M. Fridlund·A. Fukui·S. Grziwa·E. W. Guenther·A. P. Hatzes·D. Hidalgo·T. Hirano·J. Korth·M. Kuzuhara·J. Livingston·N. Narita·D. Nespral·P. Niraula·G. Nowak·E. Palle·M. Pätzold·C. M. Persson·J. Prieto-Arranz·H. Rauer·S. Redfield·I. Ribas·V. Van Eylen
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Abstract

We report the discovery from K2 of two transiting hot Jupiter systems. K2-295 (observed in Campaign 8) is a K5 dwarf which hosts a planet slightly smaller than Jupiter, orbiting with a period of 4.0 d. We have made an independent discovery of K2-237 b (Campaign 11), which orbits an F6 dwarf every 2.2 d and has an inflated radius 50 - 60 per cent larger than that of Jupiter. We use high-precision radial velocity measurements, obtained using the HARPS and FIES spectrographs, to measure the planetary masses. We find that K2-295 b has a similar mass to Saturn, while K2-237 b is a little more massive than Jupiter.

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A. M. S. Smith, Sz. Csizmadia, D. Gandolfi, S. Albrecht, R. Alonso, O. Barragán, J. Cabrera, W. D. Cochran, F. Dai, H. Deeg, Ph. Eigmüller, M. Endl, A. Erikson, M. Fridlund, A. Fukui, S. Grziwa, E. W. Guenther, A. P. Hatzes, D. Hidalgo, T. Hirano, J. Korth, M. Kuzuhara, J. Livingston, N. Narita, D. Nespral, P. Niraula, G. Nowak, E. Palle, M. Pätzold, C. M. Persson, J. Prieto-Arranz, H. Rauer, S. Redfield, I. Ribas, V. Van Eylen. 2018-07-16. K2-295 b and K2-237 b: two transiting hot Jupiters. https://doi.org/10.32023/0001-5237%2F69.2.3

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