Imaging characterization of the radial-velocity brown dwarf HD18757B

Abstract

The goal of the thesis is the characterization of the substellar companion HD18757B. Several techniques are applied to retrieve the photometric and orbital information of the object. At first, HD18757B is observed in the L' band with the imaging instrument LMIRCam mounted on the Large Binocular Telescope. This observation is based on the high contrast angular differential imaging method and is further processed with the Vortex Image Processing package. Secondly, imaging data is coupled with astrometric observation from Gaia/Hipparcos and radial velocity measurements from Sophie and Elodie to run in a Markov-Chain Monte Carlo simulation. Finally, the measured parameters are compared to the properties of brown dwarfs from evolutionary and formation models.