On the Initial Mass Function and tilt of the Fundamental Plane of massive early-type galaxies

Abstract

We investigate the most plausible stellar Initial Mass Function (IMF) and the main origin of the tilt of the Fundamental Plane (FP) for old, massive early-type galaxies. We consider a sample of 13 bright galaxies of the Coma cluster and combine our results with those obtained from a sample of 57 lens galaxies in the same luminous mass range. We estimate the luminous mass and stellar mass-to-light ratio values of the sample galaxies by fitting their SDSS multi-band photometry with composite stellar population models computed with different dust-free, solar-metallicity templates and IMFs. We compare these measurements and those derived from two-component orbit-based dynamical modelling. The photometric and dynamical luminous mass estimates of the galaxies in our sample are consistent, within the errors, if a Salpeter IMF is adopted. On the contrary, with a Kroupa or Chabrier IMF the two luminous mass diagnostics differ at a more than 4 σlevel. For the massive Coma galaxies, their stellar mass-to-light ratio scales with luminous mass as the corresponding effective quantities are observed to scale on the FP. This indicates that the tilt of the FP is primarily caused by stellar population properties. We conclude that old, massive lens and non-lens early-type galaxies obey the same luminous and dynamical scaling relations, favour a Salpeter IMF, and suggest a stellar population origin for the tilt of the FP. The validity of these results for samples of early-type galaxies with different age and mass properties still remains to be tested.

5 pages, 2 figures, accepted by MNRAS

References in corpus (7)

• Dynamical modelling of luminous and dark matter in 17 Coma early-type galaxies
• The Properties and Evolution of a K-band Selected Sample of Massive Galaxies at z~0.4 - 2 in the Palomar/DEEP2 Survey
• Comparing dynamical and photometric-stellar masses of early-type galaxies at z ~ 1
• Star formation histories of early-type galaxies at z = 1.2 in cluster and field environments
• The Star Formation Histories of Red-Sequence Galaxies, Mass-to-Light Ratios and the Fundamental Plane
• Stellar mass estimates in early-type galaxies from lensing+dynamical and photometric measurements
• A twelve-image gravitational lens system in the z ~ 0.84 cluster Cl J0152.7-1357

Cited by in corpus (40)

• The Atlas3D project - XX. Mass-size and mass-sigma distributions of early-type galaxies: bulge fraction drives kinematics, mass-to-light ratio, molecular gas fraction and stellar initial mass function
• The Sloan Lens ACS Survey. X. Stellar, Dynamical, and Total Mass Correlations of Massive Early-type Galaxies
• The Stellar Initial Mass Function in Early-Type Galaxies From Absorption Line Spectroscopy. II. Results
• Stellar mass -- halo mass relation and star formation efficiency in high-mass halos
• AGN-driven quenching of star formation: morphological and dynamical implications for early-type galaxies
• The stellar and sub-stellar IMF of simple and composite populations
• Dark Matter Contraction and the Stellar Content of Massive Early-type Galaxies: Disfavoring "Light" Initial Mass Functions
• Dynamical masses of early-type galaxies: a comparison to lensing results and implications for the stellar IMF and the distribution of dark matter
• Forming Early-Type Galaxies in LambdaCDM Simulations -I. Assembly histories
• An inventory of the stellar initial mass function in early-type galaxies
• The unexpectedly large dust and gas content of quiescent galaxies at z>1.4
• The X-Shooter Lens Survey - I. Dark-Matter Domination and a Salpeter-type IMF in a Massive Early-type Galaxy
• The inner structure of early-type galaxies in the Illustris simulation
• Dynamical versus Stellar Masses of Ultracompact Dwarf Galaxies in the Fornax Cluster
• Testing adiabatic contraction with SDSS elliptical galaxies
• A direct constraint on the gas content of a massive, passively evolving elliptical galaxy at z = 1.43
• The SWELLS survey. III. Disfavouring "heavy" initial mass functions for spiral lens galaxies
• Velocity Dispersion, Size, Sérsic Index and $D_{n}4000$: The Scaling of Stellar Mass with Dynamical Mass for Quiescent Galaxies
• The MOND Fundamental Plane
• On the average density profile of dark-matter halos in the inner regions of massive early-type galaxies
• Projected central dark matter fractions and densities in massive early-type galaxies from the Sloan Digital Sky Survey
• CLASH-VLT: a full dynamical reconstruction of the mass profile of Abell S1063 from 1 kpc out to the virial radius
• The central dark matter content of early-type galaxies: scaling relations and connections with star formation histories
• Evolution of central dark matter of early-type galaxies up to z ~ 0.8
• The last 6 Gyr of dark matter assembly in massive galaxies from the Kilo Degree Survey
• Dwarf Galaxies in the Coma Cluster: II. Spectroscopic and Photometric Fundamental Planes
• The effects of the IMF on the chemical evolution of elliptical galaxies
• CLASH: Extending galaxy strong lensing to small physical scales with distant sources highly-magnified by galaxy cluster members
• New strong lensing modelling of SDSS J2222+2745 enhanced with VLT/MUSE spectroscopy
• Is the IMF in ellipticals bottom-heavy? Clues from their chemical abundances
• Measuring the total and baryonic mass profiles of the very massive CASSOWARY 31 strong lens. A fossil system at z ~ 0.7?
• Exploring the low-mass regime of galaxy-scale strong lensing: Insights into the mass structure of cluster galaxies
• On Galaxies and Homology
• Understanding the Fundamental Plane and the Tully Fisher Relation
• Dark matter-rich early-type galaxies in the CASSOWARY 5 strong lensing system
• The central dark matter fraction of massive early-type galaxies
• The quantity of dark matter in early-type galaxies and its relation to the environment
• Cosmography from accurate mass modeling of the lens group SDSS J0100+1818: five sources at three different redshifts
• Observational dynamics of low-mass stellar systems
• Is there a tilt in the fundamental (hyper)plane?