Analysis of a XMM-Newton Spectrum of the Extremely Hot White Dwarf in   Nova V4743 Sgr
  Classical novae occur in close binary systems (main-sequence star + white dwarf). V4743 Sgr is a very fast nova exhibiting a X-ray spectrum which is consistent with a view on the optically thick atmosphere of an extremely hot white dwarf (WD). It exhibits strong absorption features of the C V, C VI, N VI, N VII, and O VII resonance lines indicating an effective temperature of about 610 kK.   We present preliminary results of a spectral analysis by means of line-blanketed non-LTE atmosphere models of a XMM-Newton RGS-1 spectrum of V4743 Sgr, taken about half a year after its outburst. 
Thomas Rauch (1 and 2), Klaus Werner (2), and Marina Orio (3 and 4)   ((1) Dr.-Remeis-Sternwarte, Bamberg, Germany, (2) Inst...