Polarization in binaries

Abstract

Theoretical models are computed for estimating linear polarization from the extended dusty outer layers of the components of a close binary system whose surfaces are distorted by rotation and mutual tidal effects. Plane-parallel layers of the dusty atmospheres of the components are assumed. A wavelength-dependent scattering coefficient and a Rayleigh phase function is used in solving the equation of radiative transfer. Polarization increases with decreasing wavelength and increasing particle size. Polarization for uniform rotation is larger than that for nonuniform rotation. Polarization for single stars is always less than that for a binary component, dependent on the position of the observer