Identification of a DO White Dwarf and a PG1159 Star in the ESO SN Ia Progenitor Survey (SPY)

We present high-resolution VLT spectra of a new DO white dwarf and a new PG1159 star, which we identified in the ESO SPY survey. The PG1159 star is a low-gravity, extremely hot (Te® = 160 000 K, log g = 6) star, having a C/He dominated atmosphere with considerable amounts of O and Ne (He=38%, C=54%, O=6%, Ne=2% by mass). It is located within the planetary nebula nuclei instability strip and pulsations have been discovered. The DO is a unique object. From He i/He ii line strengths we found Te®¼60 000 K, however, the He ii lines are extraordinarily strong and cannot be fitted by any model.