Faraday Tomography of the SS433 Jet Termination Region

• Main Authors: Haruka Sakemi, Mami Machida, Takumi Ohmura, Shinsuke Ideguchi, Yoshimitsu Miyashita, Keitaro Takahashi, Takuya Akahori, Hiroki Akamatsu, Hiroyuki Nakanishi, Kohei Kurahara, Jamie Farnes
• Format: Article
• Language: English
• Published: MDPI AG 2018-12-01
• Series: Galaxies
• Subjects: magnetic fields; polarization; jets and outflows; W50; SS433
• Online Access: https://www.mdpi.com/2075-4434/6/4/137

A jet termination region provides us with useful information about how a jet interacts with the interstellar medium. Identifying the strength and orientation of magnetic fields at the terminal is crucially important to understanding the mechanism of cosmic-ray acceleration. In this article, we report results of our Faraday-tomography analysis of the eastern region of the radio nebula W50, where a jet from the microquasar SS433 seems to terminate. We apply <i>QU</i>-fitting, a method of Faraday-tomography, to data from the Australia Telescope Compact Array (ATCA) at 1.3&#8315;3.0 GHz. In the analysis, we distinguish multiple polarized sources along the line of sight. We identify Galactic emission candidates at Faraday depths around 0 rad m^&#8722;2 and 300 rad m^&#8722;2. The Galactic emission around 0 rad m^&#8722;2 is possibly located in front of W50. We also find emission from W50 with Faraday depths between <i>&#966;</i> = &#8722;112 to 228 rad m^&#8722;2.