Seminars at FGG
Probing the ultra-hot atmosphere of KELT-9 b: multi-wavelength analysis with GIANO-B and HARPS-N
Speaker: Alessia Di Paola (INAF - Osservatorio Astronomico di Torino)
Date and time: 2025-10-06 11:30
KELT-9 b is one of the most extreme exoplanets known and a unique laboratory for studying exotic atmospheric chemistry and dynamics. Orbiting its early-A-type host star every 1.48 days, this Ultra-Hot Jupiter experiences extreme levels of stellar irradiation, resulting in an atmospheric equilibrium temperature of approximately 4000 K. Under such extreme conditions, the planet’s transmission spectrum is expected to be dominated by absorption features from various neutral and ionized atomic species, with only limited molecular signatures. In this seminar, I will present the results of a high-resolution transmission spectroscopy analysis of KELT-9b using infrared data from the GIANO-B spectrograph, complemented by optical data from HARPS-N. By cross-correlating the observed spectra with synthetic atmospheric models, I investigate the presence of atomic and molecular species in the planet’s terminator region. The analysis aims to offer new insights into the composition, structure, and dynamics of ultra-hot Jupiter atmospheres, and to demonstrate the power of multi-wavelength spectroscopy in characterizing extreme exoplanetary environments.