X-ray emission from isolated hot white dwarfs

@article{Heise1985XrayEF,
  title={X-ray emission from isolated hot white dwarfs},
  author={John Heise},
  journal={Space Science Reviews},
  year={1985},
  volume={40},
  pages={79-90}
}
  • J. Heise
  • Published 1985
  • Physics
  • Space Science Reviews
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… Expand
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References

SHOWING 1-10 OF 33 REFERENCES
Photospheric soft X-ray emission from hot DA white dwarfs
The Einstein Observatory's imaging proportional counter has detected 150-eV soft X-ray radiation from the four hot DA white dwarfs EG 187, Gr 288 and 289, and LB 1663. The observed pulse heightExpand
The soft X-ray spectrum of Sirius B - Evidence for the photospheric hypothesis
The soft X-ray spectrum of Sirius obtained by the HEAO 1 A-2 experiment is used to investigate the origin of the X-radiation from that system. It is shown that, if the emission is coronal, then theExpand
Detection of X-ray emission from stellar coronae with ANS
With the soft X-ray detector aboard the Astronomical Netherlands Satellite (ANS) we have searched for soft X-ray emission in the range 0.2--0.284 keV from hot stellar coronae. X-ray emission has beenExpand
Results from an extensive Einstein stellar survey.
We report the preliminary results of the Einstein Observatory stellar X-ray survey. To date, 143 soft X-ray sources have been identified with stellar counterparts, leaving no doubt that stars inExpand
Extreme-ultraviolet spectrophotometry of the hot DA white dwarf HZ 43: detection of He II in the stellar atmosphere
ae report a spectrum of the hot white dwarf HZ 43 in the extreme ultraviolet band from 170--500 A with a resolution of 15 A. The spectrum is marked by a prominent absorption edge at 225 A +- 15 AExpand
The atmosphere of Sirius B. II - Extreme-ultraviolet observations
The letter reports an observation of Sirius in the extreme-ultraviolet (100-1000 A) band, using a grazing-incidence telescope flown aboard the Apollo-Soyuz mission. No positive flux is detected;Expand
Discovery of a nonsolar extreme-ultraviolet source
Results are reported for observations of EUV emission from an extrasolar object which were made with a grazing-incidence telescope during the Apollo-Soyuz mission. The total energy flux in theExpand
Diffusion time scales in white dwarfs
The time scales of a few representative elements diffusion in hydrogen- and helium-rich white-dwarf envelopes are presented. The dependences on depth, the stellar mass, and effective temperature areExpand
Constraints on the corona model for Sirius B
SINCE the discovery of Sirius as a soft X-ray source1, two models have been proposed to account for the emission—thermal emission from deep layers of an almost pure hydrogen atmosphere2, and anExpand
An ultrasoft X-ray source in Coma Berenices
We have observed an intense soft X-ray source with an extraordinary spectrum in Coma Berenices, 4$sup 0$ northeast of and unassociated with the Coma cluster of galaxies. Two spectra, obtained atExpand
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