Discovery of starspots on Vega - First spectroscopic detection of surface structures on a normal A-type star

  title={Discovery of starspots on Vega - First spectroscopic detection of surface structures on a normal A-type star},
  author={Torsten Bohm and Matthias Holschneider and François Ligni{\`e}res and Pascal Petit and Monica Rainer and F. Paletou and Gregg A. Wade and Evelyne Alecian and Herv{\'e} Carfantan and Aurore Blaz{\`e}re and Giovanni M. Mirouh},
  journal={arXiv: Solar and Stellar Astrophysics},
The theoretically studied impact of rapid rotation on stellar evolution needs to be confronted with the results of high resolution spectroscopy-velocimetry observations. A weak surface magnetic field had recently been detected in the A0 prototype star Vega, potentially leading to a (yet undetected) structured surface. The goal of this article is to present a thorough analysis of the line profile variations and associated estimators in the early-type standard star Vega (A0) in order reveal… 
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