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arXiv · 2306.01321

FAST polarization mapping of the SNR VRO 42.05.01

Li Xiao·Ming Zhu·Xiao-Hui Sun·Peng Jiang·Chun Sun
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Abstract

We have obtained the polarization data cube of the VRO 42.05.01 supernova remnant at 1240 MHz using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Three-dimensional Faraday Synthesis is applied to the FAST data to derive the Faraday depth spectrum. The peak Faraday depth map shows a large area of enhanced foreground RM of ~60 rad m-2 extending along the remnant's "wing" section, which coincides with a large-scale HI shell at -20 km/s. The two depolarization patches within the "wing" region with RM of 97 rad m-2 and 55 rad m-2 coincide with two HI structures in the HI shell. Faraday screen model fitting on the Canadian Galactic Plane Survey (CGPS) 1420 MHz full-scale polarization data reveals a distance of 0.7-0.8d_{SNR} in front of the SNR with enhanced regular magnetic field there. The highly piled-up magnetic field indicates that the HI shell at -20 km/s could originate from an old evolved SNR.

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Li Xiao, Ming Zhu, Xiao-Hui Sun, Peng Jiang, Chun Sun. 2023-06-02. FAST polarization mapping of the SNR VRO 42.05.01. https://arxiv.org/abs/2306.01321

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