First Results from the CHARA Array. VII. Long-Baseline Interferometric Measurements of Vega Consistent with a Pole-On, Rapidly Rotating Star

@article{Aufdenberg2006FirstRF,
  title={First Results from the CHARA Array. VII. Long-Baseline Interferometric Measurements of Vega Consistent with a Pole-On, Rapidly Rotating Star},
  author={Jason Paul Aufdenberg and A. M{\'e}rand and Vincent Coud{\'e} du Foresto and Olivier Absil and Emmanuel di Folco and Pierre Kervella and Stephen T. Ridgway and David H. Berger and Theo A. ten Brummelaar and Harold A. Mcalister and Judit Sturmann and Laszlo Sturmann and Nils H. Turner},
  journal={The Astrophysical Journal},
  year={2006},
  volume={645},
  pages={664-675}
}
We have obtained high-precision interferometric measurements of Vega with the CHARA Array and FLUOR beam combiner in the K’ band at projected baselines between 103m and 273m. The measured visibility amplitudes beyond the first lobe are significantly weaker than expected for a slowly rotating star characterized by a single effective temperature and surface gravity. Our measurements, when compared to synthetic visibilities and synthetic spectrophotometry from a Roche-von Zeipel gravitydarkened… 

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