Space Science Reviews

, Volume 40, Issue 1–2, pp 79–90 | Cite as

X-ray emission from isolated hot white dwarfs

  • John Heise
Part I / Galactic X-ray Astronomy Section I: STellar Coronae and Isolated White Dwarfs

Abstract

Hot white dwarfs are objects that copiously emit in the Extreme Ultraviolet and soft X-ray range. They are the brightest sources seen in the Low Energy Telescope of EXOSAT, with countrates up to 25 cnts/s. in contrast to their optical and UV spectrum the total flux and spectral distribution at soft X-ray energies are highly sensitive to the effective temperature, structure and elemental composition of the dwarf's atmosphere. The imaging soft X-ray experiments onboard EXOSAT cover with large sensitivity the spectral region where the peak of emission of hot white dwarfs is expected to occur.

I here review some of the (preliminary) results obtained so far with broadband X-ray photometry on a dozen or so white dwarfs, and some of the high-resolution spectra obtained for three white dwarfs with the grating spectrometers.

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Copyright information

© D. Reidel Publishing Company 1985

Authors and Affiliations

  • John Heise
    • 1
  1. 1.Laboratory for Space Research, UtrechtUtrechtThe Netherlands

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