The matter distribution in z ~ 0.5 redshift clusters of galaxies
1 Université de Toulouse, UPS-Observatoire Midi-Pyrénées, IRAP, Toulouse, France
2 CNRS, Institut de Recherche en Astrophysique et Planétologie (IRAP), 14 avenue Edouard Belin, 31400 Toulouse, France
3 CNRS, Institut de Recherche en Astrophysique et Planétologie (IRAP), 9 avenue Colonel Roche, 31028 Toulouse Cedex 4, France
4 Departamento de Física y Astronomía, Universidad de Valparaíso, Avda. Gran Bretana 1111, Valparaíso, Chile
5 Laboratoire AIM, IRFU/Service d’Astrophysique, CEA/DSM, CNRS and Université Paris Diderot, Bât. 709, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
6 Laboratoire d’Astrophysique de Marseille (LAM), Université d’Aix-Marseille & CNRS, UMR7326, 38 rue Frédéric Joliot-Curie, 13388 Marseille Cedex 13, France
7 Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen, Denmark
Received: 17 September 2013
Accepted: 5 May 2015
We present an optical analysis of a sample of 11 clusters built from the EXCPRES sample of X-ray selected clusters at intermediate redshift (z ~ 0.5). With a careful selection of the background galaxies, we provide the mass maps reconstructed from the weak lensing by the clusters. We compare them with the light distribution traced by the early-type galaxies selected along the red sequence for each cluster. The strong correlations between dark matter and galaxy distributions are confirmed, although some discrepancies arise, mostly for merging or perturbed clusters. The average M/L ratio of the clusters is found to be M/Lr = 160 ± 60 in solar units (with no evolutionary correction), in excellent agreement with similar previous studies. No strong evolutionary effects are identified, although the small sample size reduces the significance of the result. We also provide a individual analysis of each cluster in the sample with a comparison between the dark matter, the galaxies, and the gas distributions. Some of the clusters are studied in the optical for the first time.
Key words: Gravitational lensing: weak / X-rays: galaxies: clusters / cosmology: observations / galaxies: clusters: general / dark matter
Appendix A is available in electronic form at http://www.aanda.org
Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l’Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This research also 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. Also based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.
© ESO, 2015