English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Here we study 16 planetary nebulae (PNe) in the dwarf irregular galaxy NGC205 by using GMOS@Gemini spectra to derive their physical and chemicalparameters. The chemical patterns and evolutionary tracks for 14 of our PNesuggest that there are no type I PNe among them. These PNe have an averageoxygen abundance of 12+log(O/H)=8.08$\pm$0.28, progenitor masses of2-2.5M$_{\odot}$ and thus were born ~1.0-1.7Gyr ago. Our results are in goodagreement with previous PN studies in NGC 205. The present 12+log(O/H) iscombined with our previous works and with the literature to study the PNmetallicity trends of the Local Group (LG) dwarf galaxies, in an effort toestablish the PN luminosity- and mass-metallicity relations (LZR and MZR) forthe LG dwarf irregulars (dIrrs) and dwarf spheroidals (dSphs). Previousattempts to obtain such relations failed to provide correct conclusions becausewere based on limited samples (Richer & McCall 1995; Gon\c{c}calves et al.2007). As far as we are able to compare stellar with nebular metallicities, ourMZR is in very good agreement with the slope of the MZR recently obtained forLG dwarf galaxies using spectroscopic stellar metallicities (Kirby et al.2013). Actually, we found that both dIrr and dSph galaxies follow the same MZR,at variance with the differences claimed in the past. Moreover our MZR is alsoconsistent with the global MZR of star-forming galaxies, which span a widerstellar mass range ($\sim10^6$ - $\sim10^{11}$M$\odot$).

Planetary nebulae: the universal mass-metallicity relation for Local Group dwarf galaxies and the chemistry of NGC 205