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arXiv · 1503.00062

HATS-9b and HATS-10b: Two Compact Hot Jupiters in Field 7 of the K2 Mission

R. Brahm·A. Jordán·J. D. Hartman·G. Á. Bakos·D. Bayliss·K. Penev·G. Zhou·S. Ciceri·M. Rabus·N. Espinoza·L. Mancini·M. de Val-Borro·W. Bhatti·B. Sato·T. G. Tan·Z. Csubry·L. Buchhave·T. Henning·B. Schmidt·V. Suc·R. W. Noyes·I. Papp·J. Lázár·P. Sári
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Abstract

We report the discovery of two transiting extrasolar planets by the HATSouth survey. HATS-9b orbits an old (10.8 $\pm$ 1.5 Gyr) V=13.3 G dwarf star, with a period P = 1.9153 d. The host star has a mass of 1.03 M$_{\odot}$, radius of 1.503 R$_\odot$ and effective temperature 5366 $\pm$ 70 K. The planetary companion has a mass of 0.837 M$_J$, and radius of 1.065 R$_J$ yielding a mean density of 0.85 g cm$^{-3}$ . HATS-10b orbits a V=13.1 G dwarf star, with a period P = 3.3128 d. The host star has a mass of 1.1 M$_\odot$, radius of 1.11 R$_\odot$ and effective temperature 5880 $\pm$ 120 K. The planetary companion has a mass of 0.53 M$_J$, and radius of 0.97 R$_J$ yielding a mean density of 0.7 g cm$^{-3}$ . Both planets are compact in comparison with planets receiving similar irradiation from their host stars, and lie in the nominal coordinates of Field 7 of K2 but only HATS-9b falls on working silicon. Future characterisation of HATS-9b with the exquisite photometric precision of the Kepler telescope may provide measurements of its reflected light signature.

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R. Brahm, A. Jordán, J. D. Hartman, G. Á. Bakos, D. Bayliss, K. Penev, G. Zhou, S. Ciceri, M. Rabus, N. Espinoza, L. Mancini, M. de Val-Borro, W. Bhatti, B. Sato, T. G. Tan, Z. Csubry, L. Buchhave, T. Henning, B. Schmidt, V. Suc, R. W. Noyes, I. Papp, J. Lázár, P. Sári. 2015-02-28. HATS-9b and HATS-10b: Two Compact Hot Jupiters in Field 7 of the K2 Mission. https://doi.org/10.1088/0004-6256/150/1/33

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