ARES. III. Unveiling the Two Faces of KELT-7 b with HST WFC3

ARES. III. Le dévoilement des deux faces de KELT-7b avec HST/WFC3

William Pluriel (1) , Niall Whiteford (2, 3) , Billy Edwards (4) , Quentin Changeat (4) , Kai Hou Yip (4) , Robin Baeyens (5) , Ahmed Al-Refaie (4) , Michelle Fabienne Bieger (6) , Dorian Blain (7) , Amélie Gressier (7, 8, 9) , Gloria Guilluy (10, 11) , Adam Yassin Jaziri (1) , Flavien Kiefer (8) , Darius Modirrousta-Galian (12, 13) , Mario Morvan (4) , Lorenzo Mugnai (14) , Mathilde Poveda (15, 16) , Nour Skaf (4, 7) , Tiziano Zingales (1) , Sam Wright (4) , Benjamin Charnay (7) , Pierre Drossart (7) , Jérémy Leconte (1) , Angelos Tsiaras (4) , Olivia Venot (15) , Ingo Waldmann (4) , Jean-Philippe Beaulieu (8, 17)

1 ECLIPSE 2020
2 IfA - Institute for Astronomy [Edinburgh]
3 Centre for Exoplanet Science
4 Department of Physics and Astronomy [UCL London]
5 Instituut voor Sterrenkunde [Leuven]
6 EMPS - College of Engineering, Mathematics and Physical Sciences [Exeter]
7 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics
8 IAP - Institut d'Astrophysique de Paris
9 PLANETO - LATMOS
10 Dipartimento di Fisica [Torino]
11 OATo - INAF - Osservatorio Astrofisico di Torino
12 OAPa - INAF - Osservatorio Astronomico di Palermo
13 DiFC - Dipartimento di Fisica e Chimica [Palermo]
14 Dipartimento di Fisica [Roma La Sapienza]
15 LISA (UMR_7583) - Laboratoire Interuniversitaire des Systèmes Atmosphériques
16 MDLS - Maison de la Simulation
17 School of Physical Sciences [Hobart]

We present the analysis of the hot-Jupiter KELT-7 b using transmission and emission spectroscopy from the Hubble Space Telescope (HST), both taken with the Wide Field Camera 3 (WFC3). Our study uncovers a rich transmission spectrum which 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 (CIA) and H-. KELT-7b had also been studied with other space-based instruments and we explore the effects of introducing these additional datasets. 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.

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]

William Pluriel, Niall Whiteford, Billy Edwards, Quentin Changeat, Kai Hou Yip, et al.. ARES. III. Unveiling the Two Faces of KELT-7 b with HST WFC3. The Astronomical Journal, 2020, 160 (3), pp.112. ⟨10.3847/1538-3881/aba000⟩. ⟨hal-02937302⟩