Polarization signatures of unresolved radio sources

  title={Polarization signatures of unresolved radio sources},
  author={Dominic Schnitzeler and Julie Banfield and K J Lee},
  journal={Monthly Notices of the Royal Astronomical Society},
We investigate how the imprint of Faraday rotation on radio spectra can be used to determine the geometry of radio sources and the strength and structure of the surrounding magnetic fields. We model spectra of Stokes Q and U for frequencies between 200 MHz and 10 GHz for Faraday screens with large-scale or small-scale magnetic fields external to the source. These sources can be uniform or 2D Gaussians on the sky with transverse linear gradients in rotation measure (RM), or cylinders or… 
Magnetic Field Disorder and Faraday Effects on the Polarization of Extragalactic Radio Sources
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Magnetic fields pervade the interstellar medium (ISM), but are difficult to detect and characterize. The new generation of low-frequency radio telescopes, such as the Low Frequency Array (LOFAR: a
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Large Magneto-ionic Variations toward the Galactic Center Magnetar, PSR J1745-2900
Polarized radio emission from PSR J1745−2900 has already been used to investigate the strength of the magnetic field in the Galactic center (GC), close to Sagittarius A*. Here we report how


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Magnetic fields in extragalactic radio sources.
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Complex Faraday depth structure of active galactic nuclei as revealed by broad‐band radio polarimetry
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We present maps of the sign of the Faraday Rotation measure obtained from multi-frequency radio observations made with the Very Long Baseline Array (VLBA). The Active Galactic Nuclei (AGN) considered
An understanding of cosmic magnetism requires converting the polarization properties of extragalactic radio sources into the rest-frame in which the corresponding polarized emission or Faraday
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It is shown through a high-resolution, three-dimensional smoothed particle hydrodynamics simulation of a transonic shear layer that large-scale nonlinear surface waves can form on the lobes of