Science with RISTRETTO : combining high contrast and high spectral resolution at the VLT

Séminaire IPAG de Christophe Lovis (Université de Genève), jeudi 18 mars 2021, 11h00, IPAG seminar room

RISTRETTO will be a novel high-resolution spectrograph fed by a high-performance adaptive optics system at the VLT. It will offer high spatial and spectral resolution in the visible, enabling new exoplanet and solar system science. The main science goal of RISTRETTO is reflected-light spectroscopy of exoplanets orbiting very nearby stars, among which Proxima b. A number of exoplanets of various sizes and irradiation levels will be amenable to atmospheric and surface characterization, opening the way to large population studies in reflected light at the ELT with HIRES and PCS. In addition, RISTRETTO offers several other science opportunities that need to be further developed. It is expected to play an important role in detecting and characterizing accreting protoplanets through spectrally-resolved H-alpha emission. It can also provide spatially-resolved wind and chemical composition measurements of various solar system objects, e.g. the ice giants Uranus and Neptune, and the icy moons of Jupiter and Saturn. In this talk we will present the status of the project and discuss the science cases for RISTRETTO.