ARES. III. Unveiling the Two Faces of KELT-7 b with HST WFC3
Drossart, Pierre; Beaulieu, Jean-Philippe; Changeat, Quentin; Charnay, Benjamin; Venot, Olivia; Baeyens, Robin; Leconte, Jérémy; Fabienne Bieger, Michelle; Whiteford, Niall; Skaf, Nour; Pluriel, William; Edwards, Billy; Yip, Kai Hou; Al-Refaie, Ahmed; Blain, Dorian; Gressier, Amélie; Guilluy, Gloria; Yassin Jaziri, Adam; Kiefer, Flavien; Modirrousta-Galian, Darius; Morvan, Mario; Mugnai, Lorenzo V.; Poveda, Mathilde; Zingales, Tiziano; Wright, Sam; Tsiaras, Angelos; Waldmann, Ingo
France, United Kingdom, Belgium, Italy, Australia
Abstract
We present the analysis of the hot-Jupiter KELT-7 b using transmission and emission spectroscopy from the Hubble Space Telescope, both taken with the Wide Field Camera 3. Our study uncovers a rich transmission spectrum that is consistent with a cloud-free atmosphere and suggests the presence of H2O and H-. In contrast, the extracted emission spectrum does not contain strong absorption features and, although it is not consistent with a simple blackbody, it can be explained by a varying temperature-pressure profile, collision induced absorption, and H-. KELT-7 b had also been studied with other space-based instruments and we explore the effects of introducing these additional data sets. Further observations with Hubble, or the next generation of space-based telescopes, are needed to allow for the optical opacity source in transmission to be confirmed and for molecular features to be disentangled in emission. * ARES: Ariel Retrieval of Exoplanets School.