The Ca II infrared triplet as indicator of anomalous Ca isotopic mixture in HgMn stars

@article{Castelli2004TheCI,
  title={The Ca II infrared triplet as indicator of anomalous Ca isotopic mixture in HgMn stars},
  author={Fiorella Castelli and Swetlana Hubrig},
  journal={Astronomy and Astrophysics},
  year={2004},
  volume={421},
  url={https://api.semanticscholar.org/CorpusID:119890383}
}
For the first time we present observational evidence for an anomalous isotopic structure of Ca  in mercury-manganese (HgMn) stars. The centroid wavelengths of Ca  infrared triplet lines in a number of stars have been found redshifted with respect to the centroids of the terrestrial Ca  lines. The record holder is the star HD 175640 for which the measured wavelength is consistent with Ca  being present in the atmosphere entirely in form of the heaviest stable iso- tope 48 Ca. This is a… 
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