Poster Abstracts

Name/Affiliation:  Nadiia Kostogryz (Kiepenheuer-Institut fuer Sonnenphysik)

Title:  Polarimetry of transiting exoplanetary system HD 189733.

Abstract:
We present and discuss a polarimetric effect caused by a planet transiting the stellar disk and, therefore, breaking its symmetry and resulting in linear polarization of a partially eclipsed star. Estimates of this effect for transiting planets were made only recently. In particular, we demonstrated that the maximum polarization during transit for one of the brightest transiting planets HD189733b strongly depends on the centre-to-limb variation of linear polarization for the host star. However, observational and theoretical studies of the limb polarization have been largely concentrated on the Sun. As was shown in our previous study, we expect to observe a larger centre-to-limb linear polarization for cooler stars. Here we solve the radiative transfer problem for polarized light and simulate the centre-to-limb polarization for stars of different spectral classes taking into account various opacities.