SIMBAD references

The weak line of Hg II located at 5677.10 Å is clearly detected as a 3% absorption feature in a FEROS and a UVES spectrum of the HgMn star HD 221507. In both spectra, the line has a filled-in core which might suggest stratification or weak emission. The synthesis of this Hg II feature yields a mercury excess, about +5.70 dex, for the FEROS spectrum which is about half of the +6.00 dex excess derived from the Hg II line at 3983.93 Å. In the UVES spectrum, the 5677.10 Å feature needs a larger excess of about +6.00 dex compatible with that derived from the 3983.93 Å line. A monitoring of the 5677.10 Å line should be carried out to address the variability of this line over the rotational period. No emission lines could be found in the red part of the spectra.