SIMBAD references

For the first time we present observational evidence for an anomalous isotopic structure of CaII in mercury-manganese (HgMn) stars. The centroid wavelengths of CaII infrared triplet lines in a number of stars have been found redshifted with respect to the centroids of the terrestrial CaII lines. The record holder is the star HD 175640 for which the measured wavelength is consistent with CaII being present in the atmosphere entirely in form of the heaviest stable isotope ⁴⁸Ca. This is a very striking result as ⁴⁸Ca makes up only 0.187% of the terrestrial Ca mixture.