Fluorine in extremely hot post-AGB stars
| dc.creator | Werner, K. | |
| dc.creator | Rauch, T. | |
| dc.creator | Kruk, J. W. | |
| dc.date | 2004-12-10 | |
| dc.date.accessioned | 2026-07-25T19:32:30Z | |
| dc.description | We have discovered lines of highly ionized fluorine (Fv and Fvi) in the far-UV spectra of extremely hot (Teff=85,000--150,000 K) post-AGB stars. Our sample comprises H-rich central stars of planetary nebulae as well as H-deficient PG1159 stars. We performed non-LTE calculations and find strong F overabundances (up to 10**-4 by mass, i.e., 250 times solar) in a number of PG1159 stars, while F is essentially solar in the H-rich stars. Since PG1159 stars are believed to exhibit intershell matter of the preceding AGB phase on their surface, their chemical analyses allow for a direct insight into nucleosynthesis processes during the AGB phase. The high F abundances in PG1159 stars confirm the conclusion from abundance determinations in giants, that F is synthesized in AGB stars and that the F enrichment in the intershell must be very high. | |
| dc.description | Accepted for publication in A&A, 5 pages | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0412258 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0412258 | |
| dc.identifier.uri | https://dspace.dare.co.zw/handle/123456789/65709 | |
| dc.subject | Astrophysics | |
| dc.title | Fluorine in extremely hot post-AGB stars | |
| dc.type | text |