Third-dredge-up oxygen in planetary nebulae

D. Pequignot, J.R. Walsh, A.A. Zijlstra, G. Dudziak

Research output: Contribution to journalArticle

11 Citations (Scopus)
12 Downloads (Pure)

Abstract

The planetary nebulae He 2-436 and Wray 16-423 in the Sagittarius dwarf galaxy appear to result from nearly twin stars, except that third-dredge-up carbon is more abundant in He 2-436. A thorough photoionization-model analysis implies that ratios Ne/O, S/O and Ar/O are significantly smaller in He 2-436, indicative of third-dredge-up oxygen enrichment. The enrichment of oxygen with respect to carbon is (7±4)%. Excess nitrogen inWray 16-423 suggests third dredge-up of late-CN-cycle products even in these low-mass, intermediate-metallicity stars.
Original languageEnglish
Pages (from-to)L1-L4
Number of pages4
JournalAstronomy and Astrophysics
Volume361
Issue number1
Publication statusPublished - Sep 2000

Keywords

  • nuclear reactions
  • nucleosynthesis
  • planetary nebulae
  • galaxies
  • Sagittarius
  • stars

Cite this