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arXiv · 0706.2548

WSRT Faraday tomography of the Galactic ISM at \lambda \sim 0.86 m

D. H. F. M. Schnitzeler·P. Katgert·A. G. de Bruyn
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Abstract

We investigate the distribution and properties of Faraday rotating and synchrotron emitting regions in the Galactic ISM in the direction of the Galactic anti-centre. We apply Faraday tomography to a radio polarization dataset that we obtained with the WSRT. We developed a new method to calculate a linear fit to periodic data, which we use to determine rotation measures from our polarization angle data. From simulations of a Faraday screen + noise we could determine how compatible the data are with Faraday screens. An unexpectedly large fraction of 14% of the lines-of-sight in our dataset show an unresolved main component in the Faraday depth spectrum. For lines-of-sight with a single unresolved component we demonstrate that a Faraday screen in front of a synchrotron emitting region that contains a turbulent magnetic field component can explain the data.

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D. H. F. M. Schnitzeler, P. Katgert, A. G. de Bruyn. 2007-06-18. WSRT Faraday tomography of the Galactic ISM at \lambda \sim 0.86 m. https://doi.org/10.1051/0004-6361:20077635

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