The transport of polarized synchrotron radiation in a turbulent medium

Abstract

We have developed a model to describe the transport of polarized synchrotron radiation in an optically thin source possessing small amplitude fluctuations in thermal electron density, energetic electron density, and vector magnetic field. The analysis employs an approximation termed the small phase approximation, which is similar to the first order Rytov approximation in the theory of wave propagation in a random medium. Expressions are derived relating the (observable) autocorreltions and cross-correlations of the Stokes parameters Q and U to the correlation functions of the aforementioned physical quantities. The last section of the paper is intended for observers, and describes how data from polarization maps may be used to determine the intensity and spectral characteristics of turbulence in a synchrotron source, such as a radio galaxy.