AA Dor - An Eclipsing Post Common-Envelope Binary
  AA Dor (LB 3459) is an eclipsing, close, single-lined, post common-envelope binary (PCEB) consisting of an sdOB primary star and an unseen secondary with an extraordinary small mass - formally a brown dwarf. The brown dwarf may have been a former planet which survived a common envelope phase and has even gained mass.   A recent determination of the components' masses from results of state-of-the-art NLTE spectral analysis and subsequent comparison to evolutionary tracks shows a discrepancy between masses derived from radial-velocity and the eclipse curves. Phase-resolved high-resolution and high-SN spectroscopy was carried out with FUSE in order to investigate on this problem.   We present preliminary results of an ongoing NLTE spectral analysis of FUSE spectra of the primary. 
Thomas Rauch (1 and 2), Klaus Werner (1) ((1) Dr.-Remeis-Sternwarte,   Bamberg, Germany, (2) Institut fuer Astronomie und As...