Description:
ESPLORA (Exoplanet Spectroscopy at high resolution to Probe their Lost Origins by Revealing their Atmospheric compositions) funded by Project European Union – Next Generation EU RRF M4C2 1.1 PRIN MUR 2022 project 2022CERJ49 (ESPLORA) “Finanziato dall’Unione europea- Next Generation EU, Missione 4 Componente 2.
About five-thousand confirmed extrasolar planets are known to date, but a clear and consistent picture of how they formed and evolved is still missing. In particular, the planetary systems discovered so far have revealed an astonishing diversity in both the physical parameters of individual planets and their overall architecture, including classes of exoplanets that have no analogs in the Solar System. Among these are the hot giant planets (HGPs), whose orbital configurations challenge our traditional formation and migration theories, but also make them unique targets to address and solve several theoretical issues. The extreme radiation conditions experienced by HGPs give us the opportunity to study the physics and chemistry of planetary atmospheres in a regime little affected by condensation and sinking of the less volatile species, in a way that is not possible in the Solar System or in other (cooler and/or smaller) exoplanets. This is a crucial step towards the solution of the puzzle of their origins, because valuable information about the environment where these planets formed and their subsequent migration is encoded in the chemical composition of their atmospheres.
Transmission spectroscopy, i.e. spectral time-series obtained while a planet transits its host star, is the only technique capable to reveal a complete chemical picture for planets spanning the full HGP parameter space. At high resolution, hundreds-to-thousands of lines of atomic and molecular species are resolved, so that these species can be robustly identified by line matching with synthetic atmospheric models. Nonetheless, a reliable framework for deriving the abundances of the detected species from high-resolution transmission spectra is still missing. Our ESPLORA project aims to i) build such a framework for the first time, providing a point of reference for all future studies, and ii) apply it to our proprietary spectra gathered with the GIARPS@TNG and PEPSI@LBT spectrographs, with the ultimate goal of linking the atmospheric chemistry to planet formation and migration histories.
Technically, such challenging goals require a team of experts in both transmission spectroscopy (data reduction and modeling) and computational analysis, in order to implement state-of-the-art methods based on Bayesian and Machine Learning techniques. We have assembled such a team with nine members from two UdRs and ask for two new AdR contracts.
Our project will allow us to consolidate and expand the high standard and scientific productivity in the characterization of exoplanetary atmospheres, strengthening the important role Italy is playing in the highly competitive international context of this cutting-edge research line in astrophysics.