The contribution of very massive high-redshift SWIRE galaxies to the stellar mass function

Abstract

(Abridged) We selected high-z massive galaxies at 5.8 microns, in the SWIRE ELAIS-S1 field (1 sq. deg.). Galaxies with the 1.6 microns stellar peak redshifted into the IRAC bands (z~1-3, called ``IR-peakers'') were identified. Stellar masses were derived by means of spectro-photometric fitting and used to compute the stellar mass function (MF) at z=1-2 and 2-3. A parametric fit to the MF was performed, based on a Bayesian formalism, and the stellar mass density of massive galaxies above z=2 determined. We present the first systematic study of the very-massive tail of the galaxy stellar mass function at high redshift. A total of 326 sources were selected. The majority of these galaxies have stellar masses in excess of 1e11 Msun and lie at z>1.5. The availability of mid-IR data turned out to be a valuable tool to constrain the contribution of young stars to galaxy SEDs, and thus their M(stars)/L ratio. The influence of near-IR data and of the chosen stellar library on the SED fitting are also discussed. A significant evolution is found not only for galaxies with M~1e11 Msun, but also in the highest mass bins considered. The comoving number density of these galaxies was lower by more than a factor of 10 at z=2-3, with respect to the local estimate. SWIRE 5.8 micron peakers more massive than 1.6x1e11 Msun provide 30-50% of the total stellar mass density in galaxies at z=2-3.

Accepted for publication on A&A. 31 pages. The quality of some figures has been degraded for arXiv purposes

References in corpus (12)

• The Hubble Ultra Deep Field
• The Galaxy Mass Function up to z=4 in the GOODS-MUSIC sample: into the epoch of formation of massive galaxies
• Evidence for TP-AGB stars in high redshift galaxies, and their effect on deriving stellar population parameters
• The Gemini Deep Deep Survey: III. The abundance of massive galaxies 3-6 billion years after the Big Bang
• On the Similarity between Cluster and Galactic Stellar Initial Mass Functions
• Measuring the Average Evolution of Luminous Galaxies at z<3: The Rest-frame Optical Luminosity Density, Spectral Energy Distribution, and Stellar Mass Density
• Cosmic evolution of the galaxy mass and luminosity functions by morphological type from multi-wavelength data in the CDF-South
• The XMM-Newton survey of the ELAIS-S1 field. I: Number counts, angular correlation function and X-ray spectral properties
• The ESO-Spitzer Imaging extragalactic Survey (ESIS) I: WFI B,V,R deep observations of ELAIS-S1 and comparison to Spitzer and GALEX data
• SPITZER Observations of z~3 Lyman Break Galaxies: stellar masses and mid-infrared properties
• The discovery of a significant sample of massive galaxies at redshifts 5 < z < 6 in the UKIDSS Ultra Deep Survey Early Data Release
• Keck spectroscopy of z=1-3 ULIRGs from the Spitzer SWIRE survey

Cited by in corpus (8)

• MOIRCS Deep Survey IV: Evolution of Galaxy Stellar Mass Function Back to z ~ 3
• The VVDS-SWIRE-GALEX-CFHTLS surveys: Physical properties of galaxies at z below 1.2 from photometric data
• MAMBO 1.2mm observations of luminous starbursts at z~2 in the SWIRE fields
• A Spitzer survey of Deep Drilling Fields to be targeted by the Vera C. Rubin Observatory Legacy Survey of Space and Time
• Obscured and powerful AGN and starburst activities at z~3.5
• Clustering of star-forming galaxies detected in mid-infrared with the Spitzer wide-area survey
• Multi-wavelength properties of Spitzer-selected starbursts at z~2
• The ESO-Spitzer Imaging extragalactic Survey (ESIS) II: VIMOS I,z wide field imaging of ELAIS-S1 and selection of distant massive galaxies