Another look at the dayside spectra of WASP-43b and HD 209458b: Are there scattering clouds?

Abstract

The search for clouds on the dayside of hot Jupiters has been disadvantaged due to the limited number of high quality space-based observations of their dayside. To date, retrieval studies have found no evidence for grey clouds on the dayside, however none of these studies explored the impact of scattering clouds. In this study we reanalyse the dayside emission spectrum of the hot Jupiter WASP-43b considering the different Spitzer data in the literature. We find that, in 2 of the 4 data sets explored, retrieving with a model that contains a scattering cloud is favoured over a cloud free model by a confidence of 3.13 - 3.36 σ. The other 2 data sets finds no evidence for scattering clouds. We find that the retrieved H₂O abundance is consistent regardless of the Spitzer data used and is consistent with literature values. We perform the same analysis for the hot Jupiter HD 209458b and find no evidence for dayside clouds, consistent with previous studies.