The enigmatic X-ray point sources at the central stars of NGC 6543 and NGC 7293

Martín A. Guerrero, You Hua Chu, Robert A. Gruendl, Rosa M. Williams, James B. Kaler

Research output: Contribution to journalArticle


Recent Chandra ACIS-S observations have detected a point source at the central star of NGC 6543 and confirmed the point-source nature of the hard X-ray emission from NGC 7293. The X-ray spectra of both sources peak between 0.5 and 1.0 keV and show line features indicating a thin plasma at temperatures of a few times 106 K. Their X-ray luminosities are 1030 and 3 × 1029 ergs s-1, respectively. We have considered four different mechanisms to explain the nature of these sources. The X-ray emission from the central star of NGC 6543 may originate from the coronal activity of an undetected companion star or from shocks in its fast stellar wind, while the hard X-ray emission from NGC 7293 might be ascribed to an undetected dMe companion. Follow-up observations are needed to determine the existence and natures of these stellar companions.

Original languageEnglish (US)
Pages (from-to)L55-L58
JournalAstrophysical Journal
Issue number1 PART 2
StatePublished - May 20 2001



  • Planetary nebulae: general
  • Planetary nebulae: individual (NGC 6543, NGC 7293)
  • Stars: AGB and post-AGB
  • X-rays: stars

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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