Institut für Astronomie und Astrophysik Abteilung Astronomie Sand 1, D-72076 Tübingen, Germany
Hinweis: Einige Seiten auf astro.uni-tuebingen.de können veraltet sein und werden nicht mehr aktualisiert. Note: Some webpages at astro.uni-tuebingen.de may be outdated and will no longer be updated.

Preprint 03/05

Light and heavy metal abundances in hot central stars of planetary nebulae

Werner, K. (1), Hoffmann, A.I.D. (1), Jahn, D. (1), Rauch, T. (1), Reiff, E. (1), Traulsen, I. (1), Kruk, J.W. (2), Dreizler, S. (3)

(1) Institut für Astronomie und Astrophysik, Universität Tübingen, 72076 Tübingen, Germany
(2) Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
(3) Institut für Astrophysik, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany

To be published in: Planetary Nebulae as astronomical tools, Gdansk 2005, AIP Conference Proceedings

Abstract. We present new results from our spectral analyses of very hot central stars achieved since the last IAU Symposium on planetary nebulae held in Canberra 2001. The analyses are mainly based on UV and far-UV spectroscopy performed with the Hubble Space Telescope and the Far Ultraviolet Spectroscopic Explorer but also on ground-based observations performed at the Very Large Telescope and other observatories. We report on temperature, gravity, and abundance determinations for the CNO elements of hydrogen-rich central stars. In many hydrogen-deficient central stars (spectral type PG1159) we discovered particular neon and fluorine lines, which are observed for the very first time in any astrophysical object. Their analysis strongly confirms the idea that these stars exhibit intershell matter as a consequence of a late helium-shell flash.
 

Preprint (84 kb PDF file including figures)
Astrophysics (astro-ph): astro-ph/0508108

[Home Page] [Preprints 2005] [Quick Reference] [Feedback]

| Impressum Last modified 30 Jan 2013