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arXiv · 1002.1815

Radio Polarization Observations of G319.9-0.7: A Bow-shock Nebula with an Azimuthal Magnetic Field Powered by Pulsar J1509-5850

C. -Y. Ng·B. M. Gaensler·S. Chatterjee·S. Johnston
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Abstract

We report radio polarization observations of G319.9-0.7 (MSC 319.9-0.7) at 3 and 6 cm obtained with the Australia Telescope Compact Array. The source shows a highly elongated morphology with the energetic pulsar J1509-5850 located at the tip. We found a flat radio spectrum of index α=-0.26 +/- 0.04 and a high degree of linear polarization. These results confirm G319.9-0.7 as a bow-shock pulsar wind nebula. The polarization maps suggest a helical magnetic field trailing the pulsar, with the symmetry axis parallel to the system's inferred direction of motion. This is the first time such a field geometry has been seen in a bow-shock nebula, and it may be the result of an alignment between the pulsar spin axis and its space velocity. Compared to other bow-shock examples, G319.9-0.7 exhibits very different properties in the field structure and surface brightness distribution, illustrating the large diversity of the population.

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C. -Y. Ng, B. M. Gaensler, S. Chatterjee, S. Johnston. 2010-02-09. Radio Polarization Observations of G319.9-0.7: A Bow-shock Nebula with an Azimuthal Magnetic Field Powered by Pulsar J1509-5850. https://doi.org/10.1088/0004-637x%2F712%2F1%2F596

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