2006/07/20 by L. Stanghellini, Letizia Stanghellini, M. A. Guerrero +5 · 4 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/507840
published as Astrophys.J.651:898-905,2006 · The Astrophysical Journal, in press
arxiv created 2006/07/20 · openalex publication_date 2006/11/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
This paper presents a homogeneous study of abundances in a sample of 79 northern Galactic planetary nebulae (PNe) whose morphological classes have been uniformly determined. Ionic abundances and plasma diagnostics were derived from selected optical line strengths in the literature, and elemental abundances were estimated with the ionization correction factor developed by Kingsbourgh & Barlow in 1994. We compare the elemental abundances to the final yields obtained from stellar evolution models of low- and intermediate-mass stars, and we confirm that most bipolar PNe have high nitrogen and helium abundance and are the likely progeny of stars with main-sequence mass greater than 3 M ☉ . We derive = 0.27 and discuss the implication of such a high ratio in connection with the solar neon abundance. We determine the Galactic gradients of oxygen and neon and found Δ log(O/H)/Δ R = -0.01 dex kpc -1 and Δ log(Ne/H)/Δ R = -0.01 dex kpc -1 . These flat PN gradients are irreconcilable with Galactic metallicity gradients flattening with time.