Influence of Large-Scale Perturbations in Circumstellar Disks on the Linear Polarization Parameters of UX Ori Stars

Abstract

The influence of large-scale perturbations in a circumstellar disk on the linear polarization of UX Ori stars is considered. We show that the position angle of the intrinsic linear polarization of a star surrounded by a geometrically thin flared disk cannot change significantly after the passage through the photometric minimum due to perturbations in the disk. In contrast, perturbations in a disk puffed up in the dust sublimation zone can give deflections of the plane of linear polarization of the system’s radiation up to 60°. This model allows the unusual changes in linear polarization observed in UX Ori and WW Vul after prolonged photometric minima to be explained.