Characterizing Magnetized Turbulence in M51
  We use previously published high-resolution synchrotron polarization data to
perform an angular dispersion analysis with the aim of charactering magnetized
turbulence in M51. We first analyze three distinct regions (the center of the
galaxy, and the northwest and southwest spiral arms) and can clearly discern
the turbulent correlation length scale from the width of the magnetized
turbulent correlation function for two regions and detect the imprint of
anisotropy in the turbulence for all three. Furthermore, analyzing the galaxy
as a whole allows us to determine a two-dimensional Gaussian model for the
magnetized turbulence in M51. We measure the turbulent correlation scales
parallel and perpendicular to the local mean magnetic field to be,
respectively, delta_{para} = 98 +/- 5 pc and delta_{perp} = 54 +/- 3 pc, while
the turbulent to ordered magnetic field strength ratio is found to be Bt/B0 =
1.01 +/- 0.04. These results are consistent with those of Fletcher et al.
(2011), who performed a Faraday rotation dispersion analysis of the same data,
and our detection of anisotropy is consistent with current magnetized
turbulence theories.
