A Consistent Retrieval Study of Exoplanet Transmission Spectra
Thanks mainly to the Hubble and Spitzer Space Telescopes, today there are dozens of exoplanets with multi-wavelength transmission spectra. However, despite being some of the most precise observations in existence, retrieval analyses have revealed our difficulties in establishing strong constraints on the atmospheric properties of these planets. Given the complexity of atmospheric modeling and retrieval tools, multiple independent analyses are a valuable exersize to highlight the outcome of the assumptions taken by each approach, and ultimately, enable a better understanding of transiting exoplanet observations.
Here, I will present the retrieval atmospheric analysis of a sample of gaseous exoplanets with published multi-wavelength transit observations. I will discuss the general properties of the sample and compare our results to other consistent retrieval studies from the literature. I will also discuss the difficulties that degeneracies in the observed features impose in the characterization of atmospheric properties, and the consequences that arise from modeling choices made by the researchers.