H-ATLAS: A candidate high redshift cluster/protocluster of star-forming galaxies

We investigate the region around the Planck-detected z = 3.26 gravitationally lensed galaxy HATLAS J114637.9-001132 (hereinafter HATLAS12-00) using both archival Herschel data from the H-ATLAS survey and using submm data obtained with both LABOCA and SCUBA2. The lensed source is found to be surround...

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Bibliographic Details
Authors: Clements, D. L., Zotti, G. de, Pèrez-Fournon, Ismael, Herranz, Diego, Baes, M., González-Nuevo, J., Ivison, R. J., Maddox, S. J., Oteo, I.
Format: article
Status:Published version
Publication Date:2016
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/140510
Online Access:http://hdl.handle.net/10261/140510
Access Level:Open access
Keyword:Galaxies:starburst
Submillimetre:galaxies
Galaxies:high redshift
Galaxies:clusters
Description
Summary:We investigate the region around the Planck-detected z = 3.26 gravitationally lensed galaxy HATLAS J114637.9-001132 (hereinafter HATLAS12-00) using both archival Herschel data from the H-ATLAS survey and using submm data obtained with both LABOCA and SCUBA2. The lensed source is found to be surrounded by a strong overdensity of both Herschel-SPIRE sources and submm sources. We detect 17 bright (S > ~7 mJy) sources at >4σ closer than 5 arcmin to the lensed object at 850/870 μm. 10 of these sources have good cross-identifications with objects detected by Herschel-SPIRE which have redder colours than other sources in the field, with 350 μm flux >250 μm flux, suggesting that they lie at high redshift. Submillimeter Array (SMA) observations localise one of these companions to ~1 arcsec, allowing unambiguous cross identification with a 3.6 and 4.5 μm Spitzer source. The optical/near-IR spectral energy distribution of this source is measured by further observations and found to be consistent with z > 2, but incompatible with lower redshifts. We conclude that this system may be a galaxy cluster/protocluster or larger scale structure that contains a number of galaxies undergoing starbursts at the same time.