Boötes-HiZELS: an optical to near-infrared survey of emission-line galaxies at z = 0.4–4.7
AffiliationUniv Arizona, Steward Observ
galaxies: luminosity function,mass function
galaxies: star formation
MetadataShow full item record
PublisherOXFORD UNIV PRESS
CitationBoötes-HiZELS: an optical to near-infrared survey of emission-line galaxies at z = 0.4–4.7 2017, 471 (1):629 Monthly Notices of the Royal Astronomical Society
Rights© 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society
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AbstractWe present a sample of similar to 1000 emission-line galaxies at z = 0.4-4.7 from the similar to 0.7deg(2) High-z Emission-Line Survey in the Bootes field identified with a suite of six narrow-band filters at approximate to 0.4-2.1 mu m. These galaxies have been selected on their Ly alpha (73), [O (II)] (285), H beta/[O (III)] (387) or H alpha (362) emission line, and have been classified with optical to near-infrared colours. A subsample of 98 sources have reliable redshifts from multiple narrow-band (e.g. [O (II)]-H alpha) detections and/or spectroscopy. In this survey paper, we present the observations, selection and catalogues of emitters. We measure number densities of Ly alpha, [O (II)], H beta/[O (III)] and H alpha and confirm strong luminosity evolution in star-forming galaxies from z similar to 0.4 to similar to 5, in agreement with previous results. To demonstrate the usefulness of dual-line emitters, we use the sample of dual [O (II)]-H alpha emitters to measure the observed [O (II)]/H alpha ratio at z = 1.47. The observed [O (II)]/H alpha ratio increases significantly from 0.40 +/- 0.01 at z = 0.1 to 0.52 +/- 0.05 at z = 1.47, which we attribute to either decreasing dust attenuation with redshift, or due to a bias in the (typically) fibre measurements in the local Universe that only measure the central kpc regions. At the bright end, we find that both the H alpha and Ly alpha number densities at z approximate to 2.2 deviate significantly from a Schechter form, following a power law. We show that this is driven entirely by an increasing X-ray/active galactic nucleus fraction with line luminosity, which reaches approximate to 100 per cent at line luminosities L greater than or similar to 3 x 10(44) erg s(-1).
VersionFinal published version
SponsorsLeiden University; NWO/VENI; STFC [ST/L00075X/1, ST/M001229/1]; ERC Advanced Grant DUSTYGAL ; Royal Society/Wolfson Merit Award; ERC Advanced Investigator programme New-Clusters ; NASA through the Astrophysics Data Analysis Program (ADAP) [NNX12AE20G]; ESO Telescopes at the La Silla Paranal Observatory under ESO programme [098.A-0819, 179.A-2005]; National Optical Astronomy Observatory (NOAO); [S14A-086]; [2013AN002]; [2013BN008]; [2014AC88]; [2014AN002]; [2014BN006]; [2014BC118]; [2016AN001]; [2016AN004]; [2016BN011]; [C267D]
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