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Analysis of a XMM-Newton Spectrum of the Extremely Hot White Dwarf in Nova V4743 Sgr

Thomas Rauch·Klaus Werner·Marina Orio
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Abstract

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.

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Thomas Rauch, Klaus Werner, Marina Orio. 2005-01-03. Analysis of a XMM-Newton Spectrum of the Extremely Hot White Dwarf in Nova V4743 Sgr. https://doi.org/10.1063/1.1960953

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