Probing O-enrichment in C-rich dust planetary nebulae

Journal
Date Issued
2016
Author(s)
García-Hernández, D. A.
•
•
Delgado-Inglada, G.
•
•
•
Yagüe, A.
DOI
Abstract
The abundance of O in planetary nebulae (PNe) has been historically used as a metallicity indicator of the interstellar medium (ISM), where they originated; e.g. it has been widely used to study metallicity gradients in our Galaxy and beyond. However, clear observational evidence for O self-enrichment in low-metallicity Galactic PNe with C-rich dust has been recently reported. Here, we report asymptotic giant branch (AGB) nucleosynthesis predictions for the abundances of the CNO elements and helium in the metallicity range Z☉/4 < Z < 2 Z☉. Our AGB models, with diffusive overshooting from all the convective borders, predict that O is overproduced in low-Z low-mass (∼1-3 M☉) AGB stars and nicely reproduce the recent O overabundances observed in C-rich dust PNe. This confirms that O is not always a good proxy of the original ISM metallicity and other chemical elements such as Cl or Ar should be used instead. The production of oxygen by low-mass stars should be thus considered in galactic-evolution models.
Volume
458
Issue
1
Start page
L118
Uri
Url
Issn Identifier
0035-8711
Ads BibCode
2016MNRAS.458L.118G
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

Ventura_PNe.pdf

Description
PDF editoriale
Size

232.55 KB

Format

Adobe PDF

Checksum (MD5)

235ebcc17a355b26a6fa60e14b9346d7