A detailed look at chemical abundances in the Magellanic Clouds
IAU Symposium Proceedings Series(2012)
摘要
We determine elemental abundances of He, N, O, Ne, S, and Ar in Magellanic Cloud planetary nebulae (PNe) using direct methods and a large set of observed ions, minimizing the need for ionization correction factors. In contrast to prior studies, we find a clear separation between Type I and non-Type I PNe in these low-metallicity environments, and no evidence that the O-N nucleosynthesis cycle is active in low-mass progenitors. We find that the S/O abundance ratio is anomalously low compared to H II regions, confirming the "sulfur anomaly" found for Galactic PNe. We also found that Ne/O is elevated in some cases, raising the possibility that Ne yields in low-mass AGB stars may be enhanced at low metallicity.
更多查看译文
关键词
planetary nebulae: general,ISM: abundances,galaxies: individual (LMC, SMC)
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要