Dynamical parallax of σ Ori AB: mass, distance and age

  title={Dynamical parallax of $\sigma$ Ori AB: mass, distance and age},
  author={Jos{\'e} A. Caballero},
  journal={Monthly Notices of the Royal Astronomical Society},
  • J. Caballero
  • Published 18 October 2007
  • Physics
  • Monthly Notices of the Royal Astronomical Society
The massive OB-type binary σ Ori AB is in the centre of the very young σ Orionis cluster. I have computed the most probable distances and masses of the binary for several ages using a dynamical parallax-like method. It incorporates the BVRIH-band apparent magnitudes of both components, precise orbital parameters, interstellar extinction and a widely used grid of stellar models from the literature, Kepler's third law and a χ 2 minimization. The derived distance is 334 +25 −22 pc for an age of 3… Expand

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