Title: Unravel the nature of exoplanetary atmospheres through spectroscopic characterization.
Abstract: The discovery of thousands of exoplanets with a huge range of masses, sizes, and orbits has extended the horizon of the planetary exploration. Among all the techniques used for exoplanetary characterization, the high-contrast imaging technique is meant to provide insights into those planets orbiting far away from their host stars (distance >1 AU) so that their atmospheric temperature is low enough to show different chemical and dynamical behavior. This technique has proven to be successful in studying forming young Jupiter-size planet. Possible future direct-imaging exoplanet space mission, e.g. Roman Space Telescope and HabEx will observe through high-contrast imaging the starlight reflected by exoplanets unveiling their atmospheric structure. Rayleigh scattering, molecular absorption, and scattering and absorption by atmospheric condensates determine the reflection spectra of gaseous exoplanets. Whether there exist clouds is the primary factor that controls the appearance of an exoplanet. Assuming an atmospheric elemental abundance the same as the Sun, giant exoplanets may have ammonia, water or silicate clouds in their atmospheres depending on the orbital distance from their parent stars. In this seminar, I will present the work we are conducting in observing and interpreting spectroscopic atmospheric data. Through statistical tool we are able to quantify the chemical content of an exoplanet atmosphere. In particular we are developing models that will be able to tell us more about both gaseous (e.g. Jupiter and Saturn) and rocky (e.g. Venus and Earth) planets. A particular emphasis will also be posed to modern data analysis techniques such as deep learning models as they help us to obtain reliable result faster than traditional methods.