The long period eccentric orbit of the particle accelerator HD 167971 revealed by long baseline interferometry

  title={The long period eccentric orbit of the particle accelerator HD 167971 revealed by long baseline interferometry},
  author={Micha{\"e}l De Becker and Hugues Sana and Olivier Absil and J.-B. Le Bouquin and Ronny Blomme},
  journal={Monthly Notices of the Royal Astronomical Society},
Using optical long baseline interferometry, we resolved for the first time the two wide components of HD 167971, a candidate hierarchical triple system known to efficiently accelerate particles. Our multi-epoch Very Large Telescope Interferometer observations provide direct evidence for a gravitational link between the O8 supergiant and the close eclipsing O + O binary. The separation varies from 8 to 15 mas over the 3-year baseline of our observations, suggesting that the components evolve on… Expand

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