SAC Seminar - Henriette Schwarz: characterisation of exoplanet atmospheres with ground-based high dispersion spectroscopy
Oplysninger om arrangementet
Ground-based high dispersion spectroscopy in the near-infrared is proving to be a powerful technique to characterize extrasolar planets. By resolving molecular features into individual lines, the lines can be robustly identified through line matching. The technique makes use of the changing radial velocity of the planet during the observations to separate the planetary
lines from the telluric- and stellar lines. The target planet can be observed favorably either during a transit (transmission spectroscopy) or at phases shortly before or after superior conjunction (dayside spectroscopy). Since a secondary eclipse is not required to separate the contamination from the parent star, dayside spectroscopy can also be applied to non-transiting
planets. Observations with CRIRES at VLT have been employed to successfully detect CO and H2O in a handful of hot Jupiters. The data can be used to constrain both abundances and the vertical temperature structure. Recently, high dispersion spectroscopy has been combined with high contrast imaging to measure the spin of the young extrasolar planet beta Pictoris b.