2001/01/25 by Y. -H. Chu, You-Hua Chu, M. A. Guerrero +7 · 8 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Electron temperature #Emission spectrum #Gas pressure #Point source #Ram pressure #Spectral line #Stellar, planetary, and galactic studies #Thermal #Thermal emission #astro-ph
paper · pdf · doi:10.1086/320495
15 pages, 3 figures, accepted for publication in the ApJL
arxiv created 2001/01/25 · openalex publication_date 2001/05/20 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We have obtained Chandra ACIS-S observations of NGC 6543, the Cat's Eye Nebula. The X-ray emission from NGC 6543 is clearly resolved into a point source at the central star and diffuse emission confined within the central elliptical shell and two extensions along the major axis. Spectral analysis of the diffuse component shows that the abundances of the X-ray-emitting gas are similar to those of the fast (1750 km s -1 ) stellar wind but not those of the nebula. Furthermore, the temperature of this gas is ~1.7 × 10 6 K, which is 100 times lower than the expected postshock temperature of the fast stellar wind. The combination of low temperature and wind abundances is puzzling. The thermal pressure of this hot gas is about twice the pressure in the cool nebular shell; thus, the hot gas plays an essential role in the ongoing evolution of the nebula.