Book contents
- Frontmatter
- Contents
- List of contributors
- Preface
- Part I Abundances in the Galaxy: field stars
- Part II Abundances in the Galaxy: Galactic stars in clusters, bulges and the centre
- Part III Observations – abundances in extragalactic contexts
- Part IV Stellar populations and mass functions
- 24 The stellar initial mass function of metal-rich populations
- 25 Initial-mass-function effects on the metallicity and colour evolution of disc galaxies
- 26 The metallicity of circumnuclear star-forming regions
- 27 The stellar population of bulges
- 28 The metallicity distribution of the stars in elliptical galaxies
- 29 Wolf–Rayet populations at high metallicity
- 30 The stellar populations of metal-rich starburst galaxies: the frequency of Wolf–Rayet stars
- Part V Physical processes at high metallicity
- Part VI Formation and evolution of metal-rich stars and stellar yields
- Part VII Chemical and photometric evolution beyond Solar metallicity
28 - The metallicity distribution of the stars in elliptical galaxies
Published online by Cambridge University Press: 02 December 2009
- Frontmatter
- Contents
- List of contributors
- Preface
- Part I Abundances in the Galaxy: field stars
- Part II Abundances in the Galaxy: Galactic stars in clusters, bulges and the centre
- Part III Observations – abundances in extragalactic contexts
- Part IV Stellar populations and mass functions
- 24 The stellar initial mass function of metal-rich populations
- 25 Initial-mass-function effects on the metallicity and colour evolution of disc galaxies
- 26 The metallicity of circumnuclear star-forming regions
- 27 The stellar population of bulges
- 28 The metallicity distribution of the stars in elliptical galaxies
- 29 Wolf–Rayet populations at high metallicity
- 30 The stellar populations of metal-rich starburst galaxies: the frequency of Wolf–Rayet stars
- Part V Physical processes at high metallicity
- Part VI Formation and evolution of metal-rich stars and stellar yields
- Part VII Chemical and photometric evolution beyond Solar metallicity
Summary
Elliptical galaxies probably host the most metal-rich stellar populations in the Universe. The processes leading to both the formation and the evolution of such stars are discussed in terms of a new multi-zone photochemical-evolution model, taking into account detailed nucleosynthetic yields, feedback from supernovae, Population-III stars and an initial infall episode. Moreover, the radial variations in the metallicity distributions of these stars are investigated using G-dwarf-like diagrams.
By comparing model predictions with observations, we derive a picture of galaxy formation in which the higher the mass of the galaxy, the shorter are the infall and the star-formation timescales. Therefore, the stellar component of the most massive and luminous galaxies might attain a metallicity Z ≥ Z⊙ in only 0.5 Gyr.
Each galaxy is created outside-in, i.e. the outermost regions accrete gas, form stars and develop a galactic wind very quickly, in contrast to the central core in which star formation can last up to ∼ 1.3 Gyr. This finding will be discussed in the light of recent observations of the galaxy NGC 4697 which clearly exhibits a strong radial gradient in the mean stellar [〈Mg/Fe〉] ratio.
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- The Metal-Rich Universe , pp. 270 - 275Publisher: Cambridge University PressPrint publication year: 2008