EPIC 228735255b - An eccentric 6.57 day transiting hot Jupiter in Virgo

• Published in: arXiv.org 2017-06
• Main Authors: Giles, H A C, Bayliss, D, Espinoza, N, Brahm, R, Blanco-Cuaresma, S, Shporer, A, Armstrong, D, Lovis, C, Udry, S, Bouchy, F, Marmier, M, Jordán, A, Bento, J, A Collier Cameron, Sefako, R, Cochran, W D, Rojas, F, Rabus, M, Jenkins, J S, Jones, M, Pantoja, B, Soto, M, Jensen-Clem, R, Duev, D A, Salama, M, Riddle, R, Baranec, C, Law, N M
• Format: Article
• Language: English
• Subjects: Bulk density; Eccentric orbits; Extrasolar planets; Fluxes; Gas giant planets; Ground-based observation; Jupiter; Light curve; Photometry; Planet detection; Stellar rotation
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1706.06865

We present the discovery of EPIC 228735255b, a P= 6.57 days Jupiter-mass (M\(_P\)=1.019\(\pm\)0.070 M\(_{Jup}\)) planet transiting a V=12.5 (G5-spectral type) star in an eccentric orbit (e=\(0.120^{+0.056}_{-0.046}\)) detected using a combination of K2 photometry and ground-based observations. With a radius of 1.095\(\pm\)0.018R\(_{Jup}\) the planet has a bulk density of 0.726\(\pm\)0.062\(\rho_{Jup}\). The host star has a [Fe/H] of 0.12\(\pm\)0.045, and from the K2 light curve we find a rotation period for the star of 16.3\(\pm\)0.1 days. This discovery is the 9th hot Jupiter from K2 and highlights K2's ability to detect transiting giant planets at periods slightly longer than traditional, ground-based surveys. This planet is slightly inflated, but much less than others with similar incident fluxes. These are of interest for investigating the inflation mechanism of hot Jupiters.