High-Resolution Radio Observations of the Colliding-Wind Binary WR 140

  title={High-Resolution Radio Observations of the Colliding-Wind Binary WR 140},
  author={Sean Melbourne Dougherty and Anthony J. Beasley and Mark J. Claussen and B. Ashley Zauderer and N. J. Bolingbroke},
  journal={The Astrophysical Journal},
  pages={447 - 459}
Milliarcsecond resolution Very Long Baseline Array (VLBA) observations of the archetype W-R+O star colliding-wind binary (CWB) system WR 140 are presented for 23 epochs between orbital phases 0.74 and 0.97. At 8.4 GHz, the emission in the wind-collision region (WCR) is clearly resolved as a bow-shaped arc that rotates as the orbit progresses. We interpret this rotation as due to the O star moving from southeast to approximately east of the W-R star, which leads to solutions for the orbital… 

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