Bibcode
Saviane, I.; Exter, K.; Tsamis, Y.; Gallart, C.; Péquignot, D.
Bibliographical reference
Astronomy and Astrophysics, Volume 494, Issue 2, 2009, pp.515-525
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2
2009
Journal
Citations
8
Refereed citations
6
Description
Context: A planetary nebula (PN) candidate was discovered during FORS
imaging of the Local Group dwarf galaxy Phoenix. Aims: We use
this PN to complement abundances from red-giant stars. Methods:
FORS spectroscopy was used to confirm the PN classification. Empirical
methods and photoionization modeling were used to derive elemental
abundances from the emission line fluxes and to characterize the central
star. Results: For the elements deemed most reliable for
measuring the metallicity of the interstellar medium (ISM) from which
the PN formed, [O/H] ~ -0.46 and [Ar/H] ~ -1.03. [O/H] has lower
measurement errors but greater uncertainties due to the unresolved issue
of oxygen enrichment in the PN precursor star. Conclusions:
Earlier than 2 Gyr ago (the lower limit of the derived age for the
central star) the ISM had Z = 0.002-0.008, a range slightly more
metal-rich than the one provided by stars. Comparing our PN-to-stellar
values to surveys of other dwarf Local Group galaxies, Phoenix appears
to be an outlier.
Related projects
Milky Way and Nearby Galaxies
The general aim of the project is to research the structure, evolutionary history and formation of galaxies through the study of their resolved stellar populations, both from photometry and spectroscopy. The group research concentrates in the most nearby objects, namely the Local Group galaxies including the Milky Way and M33 under the hypothesis
Martín
López Corredoira