Theoretical and numerical analysis of polarization for time-dependent radiative transfer equations

We consider the matrix-valued radiative transfer equations for the Stokes p arameters for the propagation of light through turbulent atmospheres. A Mon te Carlo method is introduced to solve the rime dependent matrix-valued rad iative transfer equations in 3D geometry. The Monte Carlo method is based o n a probabilistic representation of the radiative transfer equations involv ing an augmented scalar transport equation where the polarization parameter s are independent variables, The linear moments of the augmented transport equation with respect to the polarization parameters solve the matrix-value d radiative transfer equations. We show how polarization and depolarization effects develop in time for isotropic and unpolarized point sources, consi dered for concreteness in spherical and half-space geometries. We analyze i n detail the creation of polarization by single- and multiple-scattering ef fects. (C) 2001 Elsevier Science Ltd. All rights reserved.