Rest-frame Ultraviolet-to-Optical Properties of Galaxies at z ~ 6 and 5 in the Hubble Ultra Deep Field: from Hubble to Spitzer

Abstract

We use data from the first epoch of observations with the IRAC/Spitzer for the GOODS to detect and study a collection of LBGs at z ~ 6 to 5 in the HUDF, six of which have spectroscopic confirmation. At these redshifts, IRAC samples rest-frame optical light in the range 0.5 to 0.8 um, where the effects of dust extinction are smaller and the sensitivity to light from evolved stars is greater than at shorter, rest-frame UV observable from the ground or with the HST. As such, it provides useful constraints on the ages and masses of these galaxies' stellar populations. We find that the SEDs for many of these galaxies are best fitted by models of stellar populations with masses of a few x 1e10 M_sun, and with ages of a few hundred Myrs, values quite similar to those derived for typical LBGs at z ~ 3. When the universe was only 1 Gyr old, some galaxies had already formed a mass of stars approaching that of the present-day Milky Way, and that they started forming those stars at z > 7, and in some cases much earlier. We find that the lower limits to the space density for galaxies in this mass range are consistent with predictions from recent hydrodynamic simulations of structure formation in a LCDM universe. All objects in our samples are consistent with having solar metallicity, suggesting that they might have already been significantly polluted by metals. The values for dust reddening derived from the model fitting are low or zero, and we find that some of the galaxies have rest-frame UV colors that are even bluer than those predicted by the stellar population models to which we compare them. These colors might be attributed to the presence of very massive stars (> 100 M_sun), or by weaker intergalactic HI absorption than what is commonly assumed.

arXiv commentAccepted for publication in ApJ

References in corpus (34)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Stellar population synthesis at the resolution of 2003
• Galactic Stellar and Substellar Initial Mass Function
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• The Infrared Array Camera (IRAC) for the Spitzer Space Telescope
• The Great Observatories Origins Deep Survey: Initial Results From Optical and Near-Infrared Imaging
• Passively Evolving Early-type Galaxies at 1.4<z<2.5 in the Hubble Ultra Deep Field
• A standard stellar library for evolutionary synthesis: I. Calibration of theoretical spectra
• The Stellar Populations and Evolution of Lyman Break Galaxies
• The Rest-Frame Optical Properties of z~3 Galaxies
• A Significant Population of Red, Near-IR Selected High Redshift Galaxies
• Old Galaxies in the Young Universe
• The Rest-Frame UV Luminosity Density of Star-Forming Galaxies at Redshifts z>3.5
• IRAC Mid-Infrared Imaging of the Hubble Deep Field South: Star Formation Histories and Stellar Masses of Red Galaxies at z>2
• The Gemini Deep Deep Survey: III. The abundance of massive galaxies 3-6 billion years after the Big Bang
• The K20 survey. VI. The Distribution of the Stellar Masses in Galaxies up to z~2
• Cosmic Variance in the Great Observatories Origins Deep Survey
• The Star Formation Rate of the Universe at z~6 from the Hubble Ultra Deep Field
• Optical-IR Spectral Energy Distributions of z>2 Lyman Break Galaxies
• Color-selected galaxies at z~6 in the Great Observatories Origins Deep Survey
• The Great Observatories Origins Deep Survey - VLT/FORS2 Spectroscopy in the GOODS-South Field
• Candidates of z ~ 5.5--7 Galaxies in the HST Ultra Deep Field
• An overdensity of galaxies at z=5.9 +/-0.2 in the Ultra Deep Field confirmed using the ACS grism
• Near-Infrared Properties of I-Drop Galaxies in the Hubble Ultra Deep Field
• High-Redshift Extremely Red Objects in the HST Ultra Deep Field Revealed by the GOODS IRAC Observations
• GRAPES, Grism Spectroscopy of the Hubble Ultra Deep Field: Description and Data Reduction
• The NICMOS Ultra Deep Field: Observations, Data Reduction, and Galaxy Photometry
• Spitzer and Hubble Constraints on the Physical Properties of the z~7 Galaxy Strongly Lensed by Abell 2218
• The Major Sources of the Cosmic Reionizing Background at z ~ 6
• Possible Detection of Cosmological Reionization Sources
• Is There a Missing Galaxy Problem at High Redshift?
• The evolution of the galaxy luminosity function in the rest frame blue band up to z=3.5
• A Redshift z=5.4 Lyman alpha Emitting Galaxy with Linear Morphology in the GRAPES/UDF Field
• Photometric Estimates of Stellar Masses in High-Redshift Galaxies

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