A panchromatic study of BLAST counterparts: total star-formation rate, morphology, AGN fraction and stellar mass

Abstract

We carry out a multi-wavelength study of individual galaxies detected by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) and identified at other wavelengths, using data spanning the radio to the ultraviolet (UV). We develop a Monte Carlo method to account for flux boosting, source blending, and correlations among bands, which we use to derive deboosted far-infrared (FIR) luminosities for our sample. We estimate total star-formation rates for BLAST counterparts with z < 0.9 by combining their FIR and UV luminosities. Star formation is heavily obscured at L_FIR > 10^11 L_sun, z > 0.5, but the contribution from unobscured starlight cannot be neglected at L_FIR < 10^11 L_sun, z < 0.25. We assess that about 20% of the galaxies in our sample show indication of a type-1 active galactic nucleus (AGN), but their submillimeter emission is mainly due to star formation in the host galaxy. We compute stellar masses for a subset of 92 BLAST counterparts; these are relatively massive objects, with a median mass of ~10^11 M_sun, which seem to link the 24um and SCUBA populations, in terms of both stellar mass and star-formation activity. The bulk of the BLAST counterparts at z<1 appear to be run-of-the-mill star-forming galaxies, typically spiral in shape, with intermediate stellar masses and practically constant specific star-formation rates. On the other hand, the high-z tail of the BLAST counterparts significantly overlaps with the SCUBA population, in terms of both star-formation rates and stellar masses, with observed trends of specific star-formation rate that support strong evolution and downsizing.

Accepted for publication in the Astrophysical Journal. 44 pages, 11 figures. The SED template for the derivation of L_FIR has changed (added new figure) and the discussion on the stellar masses has been improved. The complete set of full-color postage-stamps can be found at http://blastexperiment.info/results_images/moncelsi/

References in corpus (25)

• Herschel Space Observatory - An ESA facility for far-infrared and submillimetre astronomy
• The Herschel-SPIRE instrument and its in-flight performance
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Data Processing, Sky Maps, and Basic Results
• The Cosmic Infrared Background Resolved by Spitzer. Contributions of Mid-Infrared Galaxies to the Far-Infrared Background
• The 0.4 < z < 1.3 star formation history of the Universe as viewed in the far-infrared
• Deep ATLAS radio observations of the CDFS-SWIRE field
• Photometric redshifts in the SWIRE Survey
• Over half of the far-infrared background light comes from galaxies at z >= 1.2
• Spitzer Mid-to-Far-Infrared Flux Densities of Distant Galaxies
• Spitzer Deep and Wide Legacy Mid- and Far-Infrared Number Counts and Lower Limits of Cosmic Infrared Background
• A Public, K-Selected, Optical-to-Near-Infrared Catalog of the Extended Chandra Deep Field South (ECDFS) from the MUltiwavelength Survey by Yale-Chile (MUSYC)
• The Balloon-borne Large Aperture Submillimeter Telescope: BLAST
• The VLA 1.4GHz Survey of the Extended Chandra Deep Field South: First Data Release
• The SCUBA HAlf Degree Extragalactic Survey (SHADES) -- VI. 350 micron mapping of submillimetre galaxies
• A Near-Infrared Spectroscopic Survey of K-selected Galaxies at z~2.3: Redshifts and Implications for Broadband Photometric Studies
• The SCUBA HAlf Degree Extragalactic Survey (SHADES) - VII. Optical/IR photometry and stellar masses of sub-millimeter galaxies
• The Local Universe as Seen in Far-Infrared and in Far-Ultraviolet: A Global Point of View on the Local Recent Star Formation
• The Herschel-ATLAS: Evolution of the 250um luminosity function out to z=0.5
• Calibration update of the COMBO-17 CDFS catalogue
• Star formation history of galaxies from z=0 to z=0.7 A backward approach to the evolution of star-forming galaxies
• The SCUBA Half Degree Extragalactic Survey (SHADES) - IX: the environment, mass and redshift dependence of star formation
• Radio and mid-infrared identification of BLAST source counterparts in the Chandra Deep Field South
• Star formation histories from multi-band photometry: A new approach
• A SCUBA/Spitzer Investigation of the Far Infra-Red Extragalactic Background
• A multi--wavelength study of the IRAS Deep Survey galaxy sample II. The far-IR properties

Cited by in corpus (9)

• HerMES: The Contribution to the Cosmic Infrared Background from Galaxies Selected by Mass and Redshift
• The VLA 1.4GHz Survey of the Extended Chandra Deep Field South: Second Data Release
• A Foreground Masking Strategy for [CII] Intensity Mapping Experiments Using Galaxies Selected by Stellar Mass and Redshift
• Correlations in the (Sub)millimeter background from ACTxBLAST
• Measuring star formation in high-z massive galaxies: A mid-infrared to submillimeter study of the GOODS NICMOS Survey sample
• An ALMA survey of sub-millimeter galaxies in the Extended Chandra Deep Field South: Sub-millimeter properties of color-selected galaxies
• SHARDS: A global view of the star formation activity at z~0.84 and z~1.23
• Stacked Average Far-Infrared Spectrum of Dusty Star-Forming Galaxies from the Herschel/SPIRE Fourier Transform Spectrometer
• LADUMA: Discovery of a luminous OH megamaser at $z>0.5$