Weak lensing density profiles and mass reconstructions of the galaxy clusters Abell 1351 and Abell 1995K. Holhjem1, 2, M. Schirmer1, 3, and H. Dahle2
1 Argelander-Institut für Astronomie (AIfA), Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany
2 Institute of Theoretical Astrophysics, University of Oslo, PO Box 1029 Blindern, 0315 Oslo, Norway
3 Isaac Newton Group of Telescopes, Calle Alvarez Abreu 70, 38700 Santa Cruz de La Palma, Spain
Received 6 November 2007 / Accepted 11 June 2009
Aims. The aim of the present work is to study the overall mass distribution of the galaxy clusters Abell 1351 and Abell 1995 using weak gravitational lensing. These clusters have a very different mass structure and dynamical state and are the two extremes from a larger sample of 38 X-ray luminous clusters of similar size and redshift.
Methods. We measure the shear values of faint background galaxies and correct for PSF anisotropies using the KSB+ method. Two-dimensional mass maps of the clusters are created using a finite-field mass reconstruction algorithm, and verified with aperture mass statistics. The masses inferred from the reconstructions are compared to those obtained from fitting spherically symmetric SIS- and NFW-models to the tangential shear profiles. We discuss the NFW concentration parameters in detail.
Results. From the mass reconstructions we infer -masses of and for Abell 1351 and Abell 1995, respectively. About northeast of the main mass peak of Abell 1351, we detect a significant secondary peak both in the mass reconstruction and from aperture mass statistics. This feature is also traced by cluster members selected by means of their V-I colour, and is therefore likely a real substructure of Abell 1351. From our fits to the tangential shear we infer masses of the order of (Abell 1351) and (Abell 1995). The concentration parameters remain poorly constrained by our weak lensing analysis.
Key words: gravitational lensing -- cosmology: dark matter -- galaxies: clusters: individual: Abell 1351, Abell 1995
© ESO 2009