Poster
A. R. Costa Silva, O. Demangeon, N. C. Santos, D. Ehrenreich, C. Lovis
Abstract
The extremely hot atmospheres of ultra hot Jupiters (UHJs) are excellent targets for atmospheric characterisation studies using ground-based high-resolution emission spectroscopy. We present the first high-resolution optical emission spectra for the UHJ WASP-76b. This planet was observed on four epochs with ESPRESSO (VLT), before and after its eclipse, when the dayside is in view. We searched for signatures of FeI and FeII in the dayside, which can confirm the existence of a thermal inversion layer. Furthermore, we investigate how the atmospheric profile impacts the detection. We apply cross-correlation function (CCF) techniques and detect a blueshifted (-4.6km/s) FeI signature on the dayside of WASP-76b, at 6.7-sigma (co-added CCFs) and 14.1-sigma (Kp-vsys plot). FeII was not detected, possibly due to the smaller amount of spectral lines available in the optical range. We propose that material moving radially outward from the hotspot on the dayside could explain our FeI detection.
Exoplanets5
Leiden, Netherlands
2024 June
