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
25 - Initial-mass-function effects on the metallicity and colour evolution of disc 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
In this contribution, we use chemo-dynamical models to investigate the influence of the initial mass function (IMF) on the evolution of disc galaxies, in particular of their metallicities and colours. We find that ‘bottom-light’ IMFs (IMFs with a high high-to-low-mass-stars ratio) lead to higher metallicities both in the stellar content and in the interstellar gas than do ‘top-light’ IMFs, and also to a higher star-formation rate (SFR) beginning ∼ 5 Gyr after the galaxy's birth.
Unfortunately, in terms of integrated colours and magnitudes, these two effects work in the opposite sense, the higher SFR turning the galaxy brighter and bluer, but the higher gas metallicity increasing the extinction and turning it fainter and redder, which complicates making statements about the IMF from these observables. The most likely wavelength region in which to detect IMF effects is the infrared (i.e. JHK), where the absorption overcompensates for SFR effects.
- Type
- Chapter
- Information
- The Metal-Rich Universe , pp. 249 - 254Publisher: Cambridge University PressPrint publication year: 2008