The Herschel-ATLAS Data Release 1 Paper II: Multi-wavelength counterparts to submillimetre sources

Abstract

This paper is the second in a pair of articles presenting data release 1 (DR1) of the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS), the largest single open-time key project carried out with the Herschel Space Observatory. The H-ATLAS is a wide-area imaging survey carried out in five photometric bands at 100, 160, 250, 350 and 500$\mu$m covering a total area of 600deg${}^2$. In this paper we describe the identification of optical counterparts to submillimetre sources in DR1, comprising an area of 161 deg${}^2$ over three equatorial fields of roughly 12${}^{\circ }$x4.5${}^{\circ }$ centred at 9${}^h$, 12${}^h$ and 14.5${}^h$ respectively. Of all the H-ATLAS fields, the equatorial regions benefit from the greatest overlap with current multi-wavelength surveys spanning ultraviolet (UV) to mid-infrared regimes, as well as extensive spectroscopic coverage. We use a likelihood-ratio technique to identify SDSS counterparts at r<22.4 for 250-$\mu$m-selected sources detected at $\ge$ 4$\sigma$ ($\approx$28mJy). We find `reliable' counterparts (reliability R$\ge$0.8) for 44,835 sources (39 per cent), with an estimated completeness of 73.0 per cent and contamination rate of 4.7 per cent. Using redshifts and multi-wavelength photometry from GAMA and other public catalogues, we show that H-ATLAS-selected galaxies at $z<0.5$ span a wide range of optical colours, total infrared (IR) luminosities, and IR/UV ratios, with no strong disposition towards mid-IR-classified AGN in comparison with optical selection. The data described herein, together with all maps and catalogues described in the companion paper (Valiante et al. 2016), are available from the H-ATLAS website at www.h-atlas.org.

MNRAS accepted

References in corpus (15)

• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• K-corrections and filter transformations in the ultraviolet, optical, and near infrared
• zCOSMOS: A Large VLT/VIMOS redshift survey covering 0 < z < 3 in the COSMOS field
• Detection of quiescent galaxies in a bicolor sequence from z=0-2
• The All-wavelength Extended Groth Strip International Survey (AEGIS) Data Sets
• The Detection of a Population of Submillimeter-Bright, Strongly-Lensed Galaxies
• The Complete Census of 70-um-Bright Debris Disks within the FEPS (Formation and Evolution of Planetary Systems) Spitzer Legacy Survey of Sun-like Stars
• Radial variation of attenuation and star formation in the largest late-type disks observed with GALEX
• Formation and Evolution of Planetary Systems (FEPS): Properties of Debris Dust around Solar-type Stars
• The 2dF-SDSS LRG and QSO (2SLAQ) Luminous Red Galaxy Survey
• The 2dF-SDSS LRG and QSO Survey: The spectroscopic QSO catalogue
• A joint analysis of BLAST 250--500um and LABOCA 870um observations in the Extended Chandra Deep Field South
• AEGIS20: a radio survey of the Extended Groth Strip
• Herschel-ATLAS/GAMA: a census of dust in optically selected galaxies from stacking at submillimetre wavelengths
• Colour matters: the effects of lensing on the positional offsets between optical and submillimetre galaxies in Herschel-ATLAS

Cited by in corpus (53)

• Galaxy And Mass Assembly (GAMA): the G02 field, Herschel-ATLAS target selection and Data Release 3
• Galaxy And Mass Assembly (GAMA): Data Release 4 and the z < 0.1 total and z < 0.08 morphological galaxy stellar mass functions
• The Herschel-ATLAS Data Release 1 Paper I: Maps, Catalogues and Number Counts
• The Herschel-ATLAS: a sample of 500μm-selected lensed galaxies over 600 square degrees
• The main sequence of star forming galaxies I. The local relation and its bending
• The East Asian Observatory SCUBA--2 survey of the COSMOS field: unveiling 1147 bright sub-millimeter sources across 2.6 square degrees
• The mean star formation rates of unobscured QSOs: searching for evidence of suppressed or enhanced star formation
• Dust production scenarios in galaxies at z ~ 6-8.3
• The Herschel-ATLAS Data Release 2, Paper I. Submillimeter and Far-infrared Images of the South and North Galactic Poles: The Largest Herschel Survey of the Extragalactic Sky
• The non-linear infrared-radio correlation of low-z galaxies: implications for redshift evolution, a new radio SFR recipe, and how to minimize selection bias
• The New Galaxy Evolution Paradigm Revealed by the Herschel Surveys
• No Redshift Evolution of Dust Temperatures from $0<z<2$
• VALES: I. The molecular gas content in star-forming dusty H-ATLAS galaxies up to z=0.35
• Dust continuum, CO, and [C I] 1-0 lines: self-consistent H2 mass estimates and the possibility of globally CO-dark galaxies at $z=0.35$
• The eROSITA Final Equatorial-Depth Survey (eFEDS): A multiwavelength view of WISE mid-infrared galaxies/active galactic nuclei
• A search for the lenses in the Herschel Bright Sources (HerBS) Sample
• The bright end of the infrared luminosity functions and the abundance of hyperluminous infrared galaxies
• IRAM 30m-EMIR Redshift Search of z = 3-4 Lensed Dusty Starbursts selected from the HerBS sample
• Gas Content and Kinematics in Clumpy, Turbulent Star-forming Disks
• Cosmology with the sub-millimetre galaxies magnification bias: Tomographic Analysis
• Dust and Power: Unravelling the merger - active galactic nucleus connection in the second half of cosmic history
• Estimating Photometric Redshifts for X-ray sources in the X-ATLAS field, using machine-learning techniques
• BEDE: Bayesian Estimates of Dust Evolution For Nearby Galaxies
• Cosmology with the submillimetre galaxies magnification bias: Proof of concept
• The second Herschel-ATLAS Data Release - III: optical and near-infrared counterparts in the North Galactic Plane field
• Herschel-ATLAS Data Release III: Near-infrared counterparts in the South Galactic Pole field -- Another 100,000 submillimetre galaxies
• Multi-wavelength properties of 850-$\mu$m selected sources from the North Ecliptic Pole SCUBA-2 survey
• Extreme nature of four blue-excess dust-obscured galaxies revealed by optical spectroscopy
• SHALOS: Statistical Herschel-ATLAS Lensed Objects Selection
• New-generation dust emission templates for star-forming galaxies
• A search for candidate strongly-lensed dusty galaxies in the Planck satellite catalogues
• Far-infrared emission in luminous quasars accompanied by nuclear outflows
• Over-density of SMGs in fields containing z~0.3 galaxies: magnification bias and the implications for studies of galaxy evolution
• Early Science with the Large Millimeter Telescope: a 1.1 mm AzTEC Survey of Red-$Herschel$ dusty star-forming galaxies
• Quasi-stellar objects and galaxy mass density profiles derived using the submillimetre galaxies magnification bias
• The Circumgalactic Medium of Submillimeter Galaxies. II. Unobscured QSOs within Dusty Starbursts and QSO Sightlines with Impact Parameters below 100 Kiloparsec
• Planck intermediate results. LV. Reliability and thermal properties of high-frequency sources in the Second Planck Catalogue of Compact Sources
• Galaxy cluster mass density profile derived using the submillimetre galaxies magnification bias
• The infrared-radio relation in the local universe
• A SCUBA-2 Selected Herschel-SPIRE Dropout and the Nature of this Population
• The SAMI Galaxy Survey: Disk-halo interactions in radio-selected star-forming galaxies
• VALES VIII: Weak ionized gas outflows in star-forming galaxies at $z\sim 0.15$ traced with VLT/MUSE
• The unusual ISM in Blue and Dusty Gas Rich Galaxies (BADGRS)
• Searching for Low-Redshift Hot Dust-Obscured Galaxies
• Interpreting the statistical properties of high-z extragalactic sources detected by the South Pole Telescope survey
• Dust sub-millimetre emission in green valley galaxies
• Multifrequency filter search for high redshift sources and lensing systems in Herschel-ATLAS
• The dust-star interplay in late-type galaxies at z < 0.5: forecasts for the JWST
• Methodological refinement of the submillimeter galaxy cross-correlation function measurements and their uncertainty estimation
• Improving Optical Photo-z Constraints for Dusty Star-forming Galaxies Using Submillimeter-based Priors
• The extension of the Fundamental Metallicity Relation beyond the BPT star-forming sequence: evidence for both gas accretion and starvation
• Deep ASKAP EMU Survey of the GAMA23 field: Properties of radio sources
• Pre-deployment Verification and Predicted Mapping Speed of MUSCAT