A Caltech Library Service

Disentangling a group of lensed submm galaxies at z∼2.9

MacKenzie, Todd P. and Scott, Douglas and Smail, Ian and Chapin, Edward L. and Chapman, Scott C. and Conley, A. and Cooray, Asantha and Dunlop, James S. and Farrah, D. and Fich, M. and Gibb, Andy G. and Holland, Wayne S. and Ivison, R. J. and Jenness, Tim and Kneib, Jean-Paul and Marsden, Gaelen and Richard, Johan and Robson, E. I. and Valtchanov, Ivan and Wardlow, Julie L. (2014) Disentangling a group of lensed submm galaxies at z∼2.9. Monthly Notices of the Royal Astronomical Society, 445 (1). pp. 201-212. ISSN 0035-8711. doi:10.1093/mnras/stu1623.

PDF - Published Version
See Usage Policy.

PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


MS 0451.6−0305 is a rich galaxy cluster whose strong lensing is particularly prominent at submm wavelengths. We combine new Submillimetre Common-User Bolometer Array (SCUBA)-2 data with imaging from Herschel Spectral and Photometric Imaging Receiver (SPIRE) and PACS and Hubble Space Telescope in order to try to understand the nature of the sources being lensed. In the region of the ‘giant submm arc’, we uncover seven multiply imaged galaxies (up from the previously known four), of which six are found to be at a redshift of z ∼ 2.9, and possibly constitute an interacting system. Using a novel forward-modelling approach, we are able to simultaneously deblend and fit spectral energy distributions to the individual galaxies that contribute to the giant submm arc, constraining their dust temperatures, far-infrared luminosities, and star formation rates (SFRs). The submm arc first identified by SCUBA can now be seen to be composed of at least five distinct sources, four of these within a galaxy group at z ∼ 2.9. Only a handful of lensed galaxy groups at this redshift are expected on the sky, and thus this is a unique opportunity for studying such systems in detail. The total unlensed luminosity for this galaxy group is (3.1 ± 0.3) × 10^(12) L_⊙, which gives an unlensed SFR of (450 ± 50) M_⊙ yr^(−1). This finding suggests that submm source multiplicity, due to physically associated groupings as opposed to chance alignment, extends to fainter flux densities than previously discovered. Many of these systems may also host optical companions undetected in the submm, as is the case here.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Scott, Douglas0000-0002-6878-9840
Smail, Ian0000-0003-3037-257X
Cooray, Asantha0000-0002-3892-0190
Farrah, D.0000-0003-1748-2010
Ivison, R. J.0000-0001-5118-1313
Kneib, Jean-Paul0000-0002-4616-4989
Richard, Johan0000-0001-5492-1049
Valtchanov, Ivan0000-0001-9930-7886
Wardlow, Julie L.0000-0003-2376-8971
Additional Information:© 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Accepted 2014 August 8. Received 2014 July 11; in original form 2013 December 2. This research has been supported by the Natural Sciences and Engineering Research Council of Canada. IRS acknowledges support from STFC (ST/I001573/1), a Leverhulme Fellowship, the ERC Advanced Investigator programme DUSTYGAL, and a Royal Society/Wolfson merit award. The James Clerk Maxwell Telescope is operated by the Joint Astronomy Centre on behalf of the Science and Technology Facilities Council of the United Kingdom, the National Research Council of Canada, and (until 2013 March 31) the Netherlands Organization for Scientific Research. Additional funds for the construction of SCUBA-2 were provided by the Canada Foundation for Innovation. SPIRE has been developed by a consortium of institutes led by Cardiff University (UK) and including University of Lethbridge (Canada); NAOC (China); CEA, LAM (France); IFSI, University of Padua (Italy); IAC (Spain); Stockholm Observatory (Sweden); Imperial College London, RAL, UCL-MSSL, UKATC, University of Sussex (UK); and Caltech, JPL, NHSC, University of Colorado (USA). This development has been supported by national funding agencies: CSA (Canada); NAOC (China); CEA, CNES, CNRS (France); ASI (Italy);MCINN (Spain); SNSB (Sweden); STFC, UKSA (UK); and NASA (USA). PACS has been developed by a consortium of institutes led by MPE (Germany) and including UVIE (Austria); KU Leuven, CSL, IMEC (Belgium); CEA, LAM (France);MPIA (Germany); INAF-IFSI/OAA/OAP/OAT, LENS, SISSA (Italy); IAC (Spain). This development has been supported by the funding agencies BMVIT(Austria), ESA-PRODEX(Belgium),CEA/CNES (France), DLR (Germany), ASI/INAF (Italy), and CICYT/MCYT (Spain). This research has made use of data from the HerMES project (, a Herschel Key Programme utilizing Guaranteed Time from the SPIRE instrument team, ESAC scientists, and a mission scientist. The HerMES data were accessed through the HeDaM data base ( operated by CeSAM and hosted by the Laboratoire d’Astrophysique de Marseille. This research used the facilities of the Canadian Astronomy Data Centre operated by the National Research Council of Canada with the support of the Canadian Space Agency. This work is based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Institute. STScI is operated by the association of Universities for Research in Astronomy, Inc. under the NASA contract NAS 5-26555. This work is also based (in part) on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA. The Dark Cosmology Centre is funded by the Danish National Research Council.
Funding AgencyGrant Number
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Science and Technology Facilities Council (STFC)ST/I001573/1
Leverhulme TrustUNSPECIFIED
European Research Council (ERC)UNSPECIFIED
Canada Foundation for InnovationUNSPECIFIED
Canadian Space Agency (CSA)UNSPECIFIED
National Astronomical Observatories, Chinese Academy of Sciences (NAOC)UNSPECIFIED
Commissariat à l’Energie Atomique (CEA)UNSPECIFIED
Laboratoire d'Astrophysique de Marseille (LAM)UNSPECIFIED
University of PaduaUNSPECIFIED
Stockholm ObservatoryUNSPECIFIED
Imperial College LondonUNSPECIFIED
University College LondonUNSPECIFIED
UKATC, University of SussexUNSPECIFIED
University of ColoradoUNSPECIFIED
Commissariat à l’Energie Atomique (CEA)UNSPECIFIED
Agenzia Spaziale Italiana (ASI)UNSPECIFIED
Ministerio de Ciencia e Innovación (MCINN)UNSPECIFIED
Swedish National Space Board (SNSB)UNSPECIFIED
United Kingdom Space Agency (UKSA)UNSPECIFIED
Bundesministerium für Verkehr, Innovation und Technologie (BMVIT)UNSPECIFIED
Deutsche Zentrum für Luft- und Raumfahrt (DLR)UNSPECIFIED
Agenzia Spaziale Italiana (ASI)UNSPECIFIED
Comisión Interministerial de Ciencia y Tecnología (CICYT)UNSPECIFIED
Danish National Research CouncilUNSPECIFIED
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Centre National d'Études Spatiales (CNES)UNSPECIFIED
Ministerio de Ciencia Y Tecnologia (MCYT)UNSPECIFIED
Issue or Number:1
Record Number:CaltechAUTHORS:20141201-101416620
Persistent URL:
Official Citation:MacKenzie, T. P., Scott, D., Smail, I., Chapin, E. L., Chapman, S. C., Conley, A., . . . Wardlow, J. L. (2014). Disentangling a group of lensed submm galaxies at z∼ 2.9. Monthly Notices of the Royal Astronomical Society, 445(1), 201-212. doi: 10.1093/mnras/stu1623
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:52210
Deposited By: Jason Perez
Deposited On:01 Dec 2014 22:03
Last Modified:10 Nov 2021 19:22

Repository Staff Only: item control page