Radio observations of HD 93129A: The earliest O star with the highest mass loss?

  title={Radio observations of HD 93129A: The earliest O star with the highest mass loss?},
  author={Paula Benaglia and B S Koribalski},
  journal={Astronomy and Astrophysics},
We present the results of radio continuum observations towards the open cluster Tr 14, where our main targets are the early-type O stars HD 93129A/B and HD 93128. The observations were carried out at 3 cm (8.64 GHz) and 6 cm (4.80 GHz) with the Australia Telescope Compact Array. Only HD 93129A (type O2 If*) was detected; we measure flux densities of S 3c m = 2.0 ± 0. 2m Jy andS 6c m = 4.1 ± 0.4 mJy. The resulting spectral index of α = −1.2 ± 0. 3( S ν ∝ ν α ) indicates predominantly non-thermal… Expand

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