Planetary nebulae abundances and stellar evolution
| Autor: | Jeronimo Bernard-Salas, S. R. Pottasch |
|---|---|
| Přispěvatelé: | Astronomy |
| Rok vydání: | 2006 |
| Předmět: |
HII regions
Sun : abundances OXYGEN GALACTIC GRADIENTS ARGON ABUNDANCES SULFUR chemistry.chemical_element FOS: Physical sciences Astrophysics CHLORINE Solar neon CARBON Neon Abundance (ecology) planetary nebulae : general evolution Astrophysics::Solar and Stellar Astrophysics Helioseismology Stellar evolution Astrophysics::Galaxy Astrophysics Physics Solar mass ELEMENTAL ABUNDANCES Astrophysics (astro-ph) SUN NEON Astronomy and Astrophysics ISM : abundances Planetary nebula Stars stars : abundances chemistry Space and Planetary Science Astrophysics::Earth and Planetary Astrophysics STARS |
| Zdroj: | Astronomy & astrophysics, 457(1), 189-196. EDP Sciences |
| ISSN: | 0004-6361 |
| DOI: | 10.48550/arxiv.astro-ph/0608001 |
| Popis: | A summary is given of planetary nebulae abundances from ISO measurements. It is shown that these nebulae show abundance gradients (with galactocentric distance), which in the case of neon, argon, sulfur and oxygen (with four exceptions) are the same as HII regions and early type star abundance gradients. The abundance of these elements predicted from these gradients at the distance of the Sun from the center are exactly the solar abundance. Sulfur is the exception to this; the reason for this is discussed. The higher solar neon abundance is confirmed; this is discussed in terms of the results of helioseismology. Evidence is presented for oxygen destruction via ON cycling having occurred in the progenitors of four planetary nebulae with bilobal structure. These progenitor stars had a high mass, probably greater than 5 solar masses. This is deduced from the high values of He/H and N/H found in these nebulae. Formation of nitrogen, helium and carbon are discussed. The high mass progenitors which showed oxygen destruction are shown to have probably destroyed carbon as well. This is probably the result of hot bottom burning. Comment: 9 pages, 2 Tables, 8 figures, A&A in press |
| Databáze: | OpenAIRE |
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