Magnetic-field fluctuations around the radio galaxy 3C 31
Abstract
Description
We present an analysis of the magnetic-field fluctuations in the magnetoionic medium in front of the radio galaxy 3C 31 derived from rotation-measure (RM) fits to high-resolution polarization images. We first show that the Faraday rotation must be due primarily to a foreground medium. We determine the RM structure functions for different parts of the source and infer that the simplest form for the power spectrum is a power law with a high-frequency cutoff. We also present three-dimensional simulations of RM produced by a tangled magnetic field in the hot plasma surrounding 3C 31, and show that the observed RM distribution is consistent with a spherical plasma distribution in which the radio source has produced a cavity.
5 pages, 4 figures, to appear in Extragalactic Jets: Theory and Observation from Radio to Gamma Ray, T. A. Rector and D. S. De Young (eds.), ASP Conference Series
5 pages, 4 figures, to appear in Extragalactic Jets: Theory and Observation from Radio to Gamma Ray, T. A. Rector and D. S. De Young (eds.), ASP Conference Series