Astronomy and Astrophysics – Astrophysics
Scientific paper
May 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997a%26a...321..891z&link_type=abstract
Astronomy and Astrophysics, v.321, p.891-897
Astronomy and Astrophysics
Astrophysics
6
Stars: Individual, Mass Loss, Spectroscopy, Ultraviolet Radiation, Planetary Nebulae
Scientific paper
During the ORFEUS-SPAS (Orbiting Retrievable Far and Extreme Ultraviolet Spectrometer on the Shuttle Pallet Satellite) mission STS-51, flown in September 1993, we observed, to our knowledge for the first time, the central star of the planetary nebula NGC 6543 in the far ultraviolet (90nm-115nm) wavelength region using the University of California, Berkeley spectrometer. The spectral resolution of the instrument during the flight was about 0.03nm. The observed stellar continuum energy distribution can be approximated by a modelled stellar atmosphere from Clegg and Middlemass with a temperature of 50000K and a gravity of log(g)=4.5, using an extinction of E(B-V)=0.08. In addition to narrow absorption lines of atomic species (e.g. HI, CI, NI, OI) the spectrum shows narrow absorption lines of molecular hydrogen and strong P-Cygni line profiles of the SVI (93.3nm, 94.5nm), OVI (103.2nm, 103.8nm) and PV (111.8nm, 112.8nm) resonance doublets. The analysis of these three P-Cygni line doublets using the escape probability method yields together with the consideration of the NV (123.9nm, 124.3nm), SiIV (139.4nm, 140.3nm) and CIV (154.8nm, 155.1nm) P-Cygni line doublets from IUE spectra as a mean value for the lower limit of the central star's mass loss rate 2.8x10^-9^Msun_/yr. This value for the stellar mass loss rate of the nucleus of NGC 6543 is compatible within a factor of two with the expected mass loss rate from the approximate radiation driven wind theory for an evolved star with a mass of 0.62Msun_, a luminosity of 3030Lsun_ and an effective temperature of 50000K.
Appenzeller Immo
Barnstedt Juergen
Goelz Michael
Grewing Michael
Gringel W.
No associations
LandOfFree
ORFEUS observations of SVI, OVI and PV in the stellar wind from the nucleus of NGC 6543. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with ORFEUS observations of SVI, OVI and PV in the stellar wind from the nucleus of NGC 6543., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and ORFEUS observations of SVI, OVI and PV in the stellar wind from the nucleus of NGC 6543. will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-829087