论文信息 - The Ca II infrared triplet as indicator of anomalous Ca isotopic mixture in HgMn stars

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

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 very striking result as 48 Ca makes up only 0.187% of the terrestrial Ca mixture.

F. Castelli | S. Hubrig

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