Detection of polarized light from WASP-33

VON ESSEN, C.; WOLTER, U.; CZESLA, S.; CELLONE, S. A.; SCHMITT, J. H. M. M.

Barcelona

Workshop; 17th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun; 2012

We report the detection of polarized light from the exoplanet WASP-33b. Using the dual-beam polarimeter CAFOS at Calar Alto Observatory, we applied a novel observing technique which more than tenfold increases the achievable effective exposure time for bright targets.We derive a value of approximately (2.4 ± 1) × 10−4 for the polarization of WASP-33b at maximum elongation, which is consistent with Rayleigh scattering in the planetary atmosphere. Planetary polarimetry allows to analyze planetary orbits with arbitrary inclination and, thus, to determine the true masses of planets.