Astronomy and Astrophysics – Astrophysics
Scientific paper
Jan 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995apj...439..264h&link_type=abstract
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 439, no. 1, p. 264-268
Astronomy and Astrophysics
Astrophysics
17
Absorption Spectra, Line Spectra, Mass Flow, Planetary Nebulae, Stellar Winds, Velocity Distribution, Hubble Space Telescope, Radial Velocity, Spectrum Analysis, Stellar Spectrophotometry
Scientific paper
Spectroscopic observations of the central star of the planetary nebula Abell 78 were obtained with the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope (HST) in the vicinity of the C IV lambda 1548.2, 1550.8 doublet. We find a series of narrow absorption features superposed on the broad, P Cygni stellar wind profile. These features are seen in both components of the doublet at heliocentric radial velocities of -18, -71, -131, and -192 km/s. At higher velocities, individual components are no longer distinct but, rather, merge into a continuous absorption extending to approximately -385 km/s. This is among the highest velocities ever detected for gas in a planetary nebula. The -18 km/s feature originates in an outer envelope of normal composition, while the -71 km/s feature is produced in the wind-swept shell encircling an irregular wind-blown bubble in the planetary nebula center. The hydrogen-poor ejecta of Abell 78, consisting of dense knots with wind-blown tails, are located in the bubble's interior, in the vicinity of the stellar wind termination shock. The high-velocity C IV lambda 154 absorption features can be explained as due to parcels of ejecta being accelerated to high velocities as they are swept up by the stellar wind during its interaction with dense condensations of H-poor ejecta. As the ablated material is accelerated, it will partially mix with the stellar wind, creating a mass-loaded flow. The abundance anomalies seen at the rim of the bubble attest to the transport of H-poor knot material by such a flow.
Borkowski Kazimierz J.
Harrington Patrick J.
Tsvetanov Zlatan
No associations
LandOfFree
GHRS observations of mass-loaded flows in Abell 78 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 GHRS observations of mass-loaded flows in Abell 78, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and GHRS observations of mass-loaded flows in Abell 78 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1819495