Abundance in the planetary nebulae NGC 6537 and He2-111
Autor: | Pottasch, [No Value], Beintema, DA, Feibelman, WA |
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Přispěvatelé: | Kapteyn Astronomical Institute |
Jazyk: | angličtina |
Rok vydání: | 2000 |
Předmět: |
NGC-6537
RADIO NUCLEI stars : emission-line Be NGC-6302 Astrophysics::High Energy Astrophysical Phenomena ISM : planetary nebulae : individual : He2-111 ISM : planetary nebulae : individual : NGC 6537 ISM : planetary nebulae : general stars : abundances infrared : ISM : lines and bands Astrophysics::Solar and Stellar Astrophysics SPECTRA Astrophysics::Earth and Planetary Astrophysics OBJECTS APPARENT MAGNITUDES Astrophysics::Galaxy Astrophysics STARS |
Zdroj: | Astronomy & astrophysics, 363(2), 767-778. EDP Sciences |
ISSN: | 0004-6361 |
Popis: | The ISO and IUE spectra of the bipolar planetary nebulae NGC 6537 and He2-111 are presented. These spectra are combined with the spectrum in the visual wavelength region from the nebulae to obtain a complete spectrum that is corrected for extinction. The chemical abundance of the nebulae is then determined and compared to previous determinations, The abundance of the two nebulae is quite similar. A comparison is then made with the abundance of two other bipolar planetary nebulae whose abundance is also determined with the help of ISO observations. It is shown that not all bipolar nebulae have similar abundance. NGC 6445 has a much lower nitrogen to oxygen ratio, similar to NGC 7027, but still not as low as the Orion nebula. |
Databáze: | OpenAIRE |
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