Exocomets in the circumstellar gas disk of HD 172555

  title={Exocomets in the circumstellar gas disk of HD 172555},
  author={Flavien Kiefer and Alain Lecavelier des Etangs and Jean Augereau and Alfred Vidal-Madjar and Anne-Marie Lagrange and Herv'e Beust},
  journal={Astronomy and Astrophysics},
The source HD 172555 is a young A7V star surrounded by a debris disk with a gaseous component. Here, we present the detection of variable absorption features detected simultaneously in the Ca II K and H doublet lines (at λ3933 A and λ3968 A). We identified the presence of these absorption signatures at four different epochs in the 129 HARPS high-resolution spectra gathered between 2004 and 2011. These transient absorption features are most likely due to falling evaporating bodies (FEBs, or… Expand

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