Resolving the Effects of Rotation in Altair with Long-Baseline Interferometry

  title={Resolving the Effects of Rotation in Altair with Long-Baseline Interferometry},
  author={Deane M. Peterson and Christian A. Hummel and Thomas A. Pauls and J. T. Armstrong and J. A. Benson and G. Charmaine Gilbreath and Robert B. Hindsley and Donald J. Hutter and Kenneth J. Johnston and David Mozurkewich and Henrique R. Schmitt},
  journal={The Astrophysical Journal},
  pages={1087 - 1097}
We report the successful fitting of a Roche model, with a surface temperature gradient following the von Zeipel gravity darkening law, to observations of Altair made with the Navy Prototype Optical Interferometer. We confirm the claim by Ohishi et al. that Altair displays an asymmetric intensity distribution due to rotation, the first such detection in an isolated star. Instrumental effects due to the high visible flux of this first magnitude star appear to be the limiting factor in the… 

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