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arXiv · 1508.00746

Ring Nebulae: Tracers of the CNO Nucleosynthesis

A. Mesa-Delgado·C. Esteban·J. García-Rojas
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Abstract

Preliminary results are presented from spectroscopic data in the optical range of the Galactic ring nebulae NGC 6888, G2:4+1:4, RCW 58 and Sh2-308. Deep observations with long exposure times were carried out at the 6.5m Clay Telescope and at the 10.4m Gran Telescopio Canarias. In NGC 6888, recombination lines of C II, O II and N II are detected with signal-to-noise ratios higher than 8. The chemical content of NGC 6888 is discussed within the chemical enrichment predicted by evolution models of massive stars. For all nebulae, a forthcoming work will content in-depth details about observations, analysis and final results (Esteban et al. 2015, in prep.).

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A. Mesa-Delgado, C. Esteban, J. García-Rojas. 2015-08-04. Ring Nebulae: Tracers of the CNO Nucleosynthesis. https://arxiv.org/abs/1508.00746

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