The CHEWIE survey of exoplanet transmission spectra
Wednesday 4 July, 12:50
During planetary transit, stellar light is filtered through an exoplanet's atmosphere, revealing the planet's atmospheric properties as wavelength-dependent absorption features. Transmission spectra obtained though spectroscopic observations of transits are today providing key information on the composition and structure of planetary atmospheres. Further, as observations become more numerous, they allow us to investigate the diversity of exoplanetary atmospheres.
While transmission spectra have long been dominated by space-based observations, recent improvements in instrumentation and analysis techniques have placed ground-based observatories at the forefront of exoplanet characterization.
I will present CHEWIE (Clouds, Hazes and Elements vieWed on gIant Exoplanets), a survey of exoplanet transmission spectra with 8m-class ground-based telescopes. I will give an overview on the survey and present recent results. The latter include the first transmission spectrum of WASP-103b, one of the most massive (1.5 MJ) and hottest (2500 K) planets characterized so far using transmission spectroscopy, and the transmission spectra of several planets in the Neptune to Saturn mass range.