Variations of the initial mass function in semi-analytical models: implications for the mass assembly and the chemical enrichment of galaxies in the GAEA model

Abstract

In this work, we investigate the implications of the Integrated Galaxy-wide stellar Initial Mass Function (IGIMF) approach in the framework of the semi-analytic model GAEA (GAlaxy Evolution and Assembly), which features a detailed treatment of chemical enrichment and stellar feedback. The IGIMF provides an analytic description of the dependence of the stellar IMF shape on the rate of star formation in galaxies. We find that our model with a universal IMF predicts a rather flat [$\alpha$/Fe]-stellar mass relation. The model assuming the IGIMF, instead, is able to reproduce the observed increase of $\alpha$-enhancement with stellar mass, in agreement with previous studies. This is mainly due to the fact that massive galaxies are characterized by larger star formation rates at high-redshift, leading to stronger $\alpha$-enhancement with respect to low-mass galaxies. At the same time, the IGIMF hypothesis does not affect significantly the trend for shorter star formation timescales for more massive galaxies. We argue that in the IGIMF scenario the [$\alpha$/Fe] ratios are good tracers of the highest star formation events. The final stellar masses and mass-to-light-ratio of our model massive galaxies are larger than those estimated from the synthetic photometry assuming a universal IMF, providing a self-consistent interpretation of similar recent results, based on dynamical analysis of local early type galaxies.

14 pages, 8 figures, 2 tables, submitted to MNRAS

References in corpus (25)

• Overview of the SDSS-IV MaNGA Survey: Mapping Nearby Galaxies at Apache Point Observatory
• The hierarchical formation of the brightest cluster galaxies
• The Mass-Metallicity Relation at z~2
• Gusty, gaseous flows of FIRE: galactic winds in cosmological simulations with explicit stellar feedback
• A systematic variation of the stellar initial mass function in early-type galaxies
• Analytical theory for the initial mass function: CO clumps and prestellar cores
• The SAMI Galaxy Survey: instrument specification and target selection
• CALIFA: a diameter-selected sample for an integral field spectroscopy galaxy survey
• The Galaxy and its stellar halo: insights on their formation from a hybrid cosmological approach
• WFCAM, Spitzer-IRAC and SCUBA observations of the massive star forming region DR21/W75: I. The collimated molecular jets
• Galaxy assembly, stellar feedback and metal enrichment: the view from the GAEA model
• Converting H$\alpha$ Luminosities into Star Formation Rates
• The stellar population histories of early-type galaxies. III. The Coma Cluster
• The Dependence of Galaxy Formation on Cosmological Parameters: Can we distinguish the WMAP1 and WMAP3 Parameter Sets?
• The SINFONI Nearby Elliptical Lens Locator Survey: Discovery of two new low-redshift strong lenses and implications for the initial mass function in giant early-type galaxies
• Diffuse stellar component in galaxy clusters and the evolution of the most massive galaxies at z<~1
• Metal Enrichment of the ICM: a 3-D Picture of Chemical and Dynamical Properties
• Variations in the initial mass function in early-type galaxies: A critical comparison between dynamical and spectroscopic results
• Elemental Abundances in Milky Way-like Galaxies from a Hierarchical Galaxy Formation Model
• The origin of the $\alpha$-enhancement of massive galaxies
• Strong Gravitational Lensing and the Stellar IMF of Early-type Galaxies
• The inferred evolution of the cold gas properties of CANDELS galaxies at 0.5 < z < 3.0
• From Discs to Bulges: effect of mergers on the morphology of galaxies
• On the dependence of galaxy morphologies on galaxy mergers
• Variations of the Initial Mass Function in Semi-Analytical models

Cited by in corpus (52)

• De Re Metallica: The cosmic chemical evolution of galaxies
• The dust content of galaxies from z = 0 to z = 9
• The impact of the metallicity and star formation rate on the time-dependent galaxy-wide stellar initial mass function
• The Dawes Review 8: Measuring the Stellar Initial Mass Function
• Very high redshift quasars and the rapid emergence of super-massive black holes
• The optimally-sampled galaxy-wide stellar initial mass function - Observational tests and the publicly available GalIMF code
• Timing the formation and assembly of early-type galaxies via spatially resolved stellar populations analysis
• MUSE observations of M87: radial gradients for the stellar initial-mass function and the abundance of Sodium
• Physical properties of SDSS satellite galaxies in projected phase-space
• Galaxy evolution across environments as probed by the ages, stellar metallicities and [alpha/Fe] of central and satellite galaxies
• The influence of environment on satellite galaxies in the GAEA semi-analytic model
• The Rise of Active Galactic Nuclei in the GAlaxy Evolution and Assembly semi-analytic model
• Stellar Metallicities and Elemental Abundance Ratios of z~1.4 Massive Quiescent Galaxies
• Tracing the Quenching Journey across Cosmic Time
• The impact of an evolving stellar initial mass function on early galaxies and reionisation
• Validating Semi-Analytic Models of High-Redshift Galaxy Formation using Radiation Hydrodynamical Simulations
• The formation of UCDs and massive GCs: Quasar-like objects for testing for a variable stellar initial mass function (IMF)
• New Analytic Solutions for Galaxy Evolution: Gas, Stars, Metals and Dust in local Early-Type Galaxies and in their high-z Starforming Progenitors
• The effect of the environment-dependent IMF on the formation and metallicities of stars over the cosmic history
• Chemical evolution of elliptical galaxies with a variable IMF -- A publicly available code
• Calibrated, cosmological hydrodynamical simulations with variable IMFs I: Method and effect on global galaxy scaling relations
• The evolution of the UV-to-mm extragalactic background light: evidence for a top-heavy initial mass function?
• The origin of discrete multiple stellar populations in globular clusters
• AGN feedback and the origin of the $\alpha$ enhancement in early type galaxies - insights from the GAEA model
• Chemical evolution of disc galaxies from cosmological simulations
• The effects of the IMF on the chemical evolution of elliptical galaxies
• ZFIRE: Using H$\alpha$ equivalent widths to investigate the in situ initial mass function at z~2
• Was the Milky Way a chain galaxy? Using the IGIMF theory to constrain the thin-disk star formation history and mass
• The Influence of Galaxy Environment on the Stellar Initial Mass Function of Early-Type Galaxies
• On the shape and evolution of a cosmic ray regulated galaxy-wide stellar initial mass function
• Non-Universal Stellar Initial Mass Functions: Large Uncertainties in Star Formation Rates at $z\approx 2-4$ and Other Astrophysical Probes
• Is the IMF in ellipticals bottom-heavy? Clues from their chemical abundances
• Nuclear vs. Integrated Spectroscopy of Galaxies in the Herschel Reference Survey
• Merger-driven evolution of the effective stellar initial mass function of massive early-type galaxies
• The galaxy-wide stellar initial mass function in the presence of cluster-to-cluster IMF variations
• BiPoS1 -- a computer programme for the dynamical processing of the initial binary star population
• Mild radial variations of the stellar IMF in the bulge of M31
• Understanding the chemical evolution of blue Edge-on Low Surface Brightness Galaxies
• Stellar population synthesis models with a physically varying IMF
• Starburst galaxies in semi-analytic models of galaxy formation and evolution
• Simple interpolation functions for the galaxy-wide stellar initial mass function and its effects in early-type galaxies
• Stellar velocity dispersion and initial mass function gradients in dissipationless galaxy mergers
• Variation of the stellar initial mass function in semi-analytical models III: testing the cosmic ray regulated integrated galaxy-wide initial mass function
• On the variation in stellar $\alpha$-enhancements of star-forming galaxies in the EAGLE simulation
• Euclid preparation. Exploring the properties of proto-clusters in the Simulated Euclid Wide Survey
• A Global Census of Metals in the Universe
• The star formation timescale of elliptical galaxies -- Fitting [Mg/Fe] and total metallicity simultaneously
• Dark-matter-induced transients over cosmic time: The role of star formation history profiles
• What triggers type Ia supernovae: Prompt detonations from primordial black holes or companion stars?
• Downsizing revised: Star formation timescales for elliptical galaxies with an environment-dependent IMF and number of SNIa
• Variations of the stellar Initial Mass Function in Semi-Analytic Models: implications for the mass assembly of galaxies in the GAEA model
• Differences between the globular cluster systems of the Virgo and Fornax Galaxy Clusters