A Caltech Library Service

XMM-LSS discovery of a z = 1.22 galaxy cluster

Bremer, M. N. and Valtchanov, I. and Willis, J. and Altieri, B. and Andreon, S. and Duc, P. A. and Fang, F. and Jean, C. and Lonsdale, C. and Pacaud, F. and Pierre, M. and Shupe, D. L. and Surace, J. A. and Waddington, I. (2006) XMM-LSS discovery of a z = 1.22 galaxy cluster. Monthly Notices of the Royal Astronomical Society, 371 (3). pp. 1427-1434. ISSN 0035-8711. doi:10.1111/j.1365-2966.2006.10767.x.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present details of the discovery of XLSS J022303.0−043622, a z= 1.2 cluster of galaxies. This cluster was identified from its X-ray properties and selected as a z > 1 candidate from its optical/near-infrared (IR) characteristics in the XMM Large-Scale Structure Survey (XMM-LSS). It is the most distant system discovered in the survey to date. We present ground-based optical and near-IR observations of the system carried out as part of the XMM-LSS survey. The cluster has a bolometric X-ray luminosity of 1.1 ± 0.7 × 10^44 erg s^−1 , fainter than most other known z > 1 X-ray selected clusters. In the optical it has a remarkably compact core, with at least a dozen galaxies inside a 125 kpc radius circle centred on the X-ray position. Most of the galaxies within the core, and those spectroscopically confirmed to be cluster members, have stellar masses similar to those of massive cluster galaxies at low redshift. They have colours comparable to those of galaxies in other z > 1 clusters, consistent with showing little sign of strong ongoing star formation. The bulk of the star formation within the galaxies appears to have ceased at least 1.5 Gyr before the observed epoch. Our results are consistent with massive cluster galaxies forming at z > 1 and passively evolving thereafter. We also show that the system is straightforwardly identified in Spitzer/IRAC 3.6- and 4.5-μm data obtained by the Spitzer Wide-area Infrared Extragalactic (SWIRE) survey emphasizing the power and utility of joint XMM and Spitzer searches for the most distant clusters.

Item Type:Article
Related URLs:
URLURL TypeDescription
Valtchanov, I.0000-0001-9930-7886
Lonsdale, C.0000-0003-0898-406X
Shupe, D. L.0000-0003-4401-0430
Surace, J. A.0000-0001-7291-0087
Additional Information:© 2006 The Authors. Journal compilation © 2006 RAS. Accepted 2006 July 4. Received 2006 June 30; in original form 2005 November 4. XMM is an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work was based on observations made with ESO Telescopes at the La Silla and Paranal Observatories under programme IDs 70.A-0733 and 074.A-0360 and with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the CFHT which is operated by the National Research Council (NRC) of Canada, the Institut National des Science de l’Univers of the Centre National de la Recherche Scientifique (CNRS) of France and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the CFHTLS, a collaborative project of NRC and CNRS. Support for SWIRE, part of the Spitzer Space Telescope Legacy Science Program, was provided by NASA through an award issued by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. This work was also supported by the European Community RTN Network POE (grant nr. HPRN-CT-2000-00138). MNB acknowledges Leverhulme Trust funding for the early part of this work. SA acknowledges financial contribution from contract ASI-INAF I/023/05/0. We thank Roberto de Propris for useful discussions.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
European Space AgencyUNSPECIFIED
European Southern Observatory70.A-0733
European Southern Observatory074.A-0360
Canada France Hawaii TelescopeUNSPECIFIED
National Research Council (NRC) of CanadaUNSPECIFIED
Institut national des sciences de l'Univers (INSU)UNSPECIFIED
University of HawaiiUNSPECIFIED
European CommunityHPRN-CT-2000-00138
Leverhulme TrustUNSPECIFIED
Agenzia Spaziale Italiana (ASI)I/023/05/0
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Subject Keywords:galaxies: clusters: general; large-scale structure of Universe
Issue or Number:3
Record Number:CaltechAUTHORS:BREmnras06
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:12345
Deposited By: Tony Diaz
Deposited On:11 Dec 2008 18:17
Last Modified:08 Nov 2021 22:27

Repository Staff Only: item control page