A First Analysis of Rosat Pointed Observations of two DA White Dwarfs

  • S. Jordan
  • R. Napiwotzki
  • K. Werner
  • D. Koester
Part of the NATO ASI Series book series (ASIC, volume 403)

Abstract

The analysis of ROSAT observations shows that the X-ray flux of the hot white dwarf HS1234+4811 cannot be explained by homogeneous H+He atmospheres. Better agreement is achieved under the assumption that the photosphere consist of an ultra-thin hydrogen layer on top of the He envelope or that heavier elements are responsible for the absorption in the soft X-ray region. On the other hand the interpretation of the ROSAT data from GD659 is possible with homogeneous H+He model atmospheres.

Keywords

Count Rate White Dwarf Column Density Pulse Height Spectrum Hydrogen Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 1993

Authors and Affiliations

  • S. Jordan
    • 1
  • R. Napiwotzki
    • 1
  • K. Werner
    • 1
  • D. Koester
    • 2
  1. 1.Institut für Theoretische Physik und Sternwarte der Universität KielKiel 1Germany
  2. 2.Dept. of Physics & AstronomyLouisiana State UniversityBaton RougeUSA

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