Letter to the Editor Four magnetic DB white dwarfs discovered by the Hamburg/ESO survey

We report on seven peculiar faint blue stars found in the course of the Hamburg/ESO survey (HES) which appear to be magnetic white dwarfs (WDs) with non-hydrogen spectra. We show in particular that four of them (HE 0338–3853, HE 0107–0158, HE 0026–2150, and HE 0003–5701) have He I lines split by magnetic fields of roughly 20 MG, since the π components of He I 5876 Å and He I 4929 Å can be identified unambiguously in their spectra, and the σ+, σ− components can be identified in the spectra of two of these stars (HE 0338– 3853 and HE 0003–5701). Besides GD 229, these are the first magnetic DB white dwarfs discovered so far. In addition, three further WDs with broad, unidentifiable features have been found: HE 1043–0502, HE 0236–2656, and HE 0330–0002. We argue that in all three of these stars H I can not be responsible for the broad features, and He I most probably not for the features in HE 0236–2656 and HE 0330– 0002, while it still remains possible that the broad features of HE 1043–0502 are due to He I.