2002/06/30 by Haakon Dahle, Hkon Dahle, Steen Hannestad +2 · 3 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Scientific Research and Discoveries #astro-ph
paper · pdf · doi:10.1086/375697
published as Astrophys.J. 588 (2003) L73 · 4 pages, 3 figures; version accepted for publication by ApJ Letters. Three figures omitted to allow space for new fig. 3 and expanded results and discussion sections, including NSIS model fit
arxiv created 2003/04/04 · openalex publication_date 2003/04/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We measure the average gravitational shear profile of six massive clusters ( M vir ~ 10 15 M ☉ ) at z = 0.3 out to a radius of ~2 h -1 Mpc. The measurements are fitted to a generalized Navarro-Frenk-White-like halo model ρ( r ) with an arbitrary r → 0 slope, α. The data are well fitted by such a model with a central cusp with α ~ 0.9-1.6 (68% confidence interval). For the standard Navarro-Frenk-White case α = 1.0, we find a concentration parameter c vir that is consistent with recent predictions from high-resolution cold dark matter N -body simulations. Our data are also well fitted by an isothermal sphere model with a softened core. For this model, our 1 σ upper limit for the core radius corresponds to a limit σ ⋆ ≤ 0.1 cm 2 g -1 on the elastic collision cross section in a self-interacting dark matter model.