%0 Journal Article
%T Inner dark matter distribution of the Cosmic Horseshoe (J1148+1930) with gravitational lensing and dynamics
%A A. Halkola
%A A. Sonnenfeld
%A A. Y£¿ld£¿r£¿m
%A G. Chiriv¨¬
%A G. F. Lewis
%A S. H. Suyu
%A S. Schuldt
%J -
%D 2019
%R 10.1051/0004-6361/201935042
%X We present a detailed analysis of the inner mass structure of the Cosmic Horseshoe (J1148+1930) strong gravitational lens system observed with the <i>Hubble<i/> Space Telescope (HST) Wide Field Camera 3 (WFC3). In addition to the spectacular Einstein ring, this systems shows a radial arc. We obtained the redshift of the radial arc counterimage <i>z<i/><sub>s,£¿r<sub/>£¿=£¿1.961£¿¡À£¿0.001 from Gemini observations. To disentangle the dark and luminous matter, we considered three different profiles for the dark matter (DM) distribution: a power law profile, the Navarro, Frenk, and White (NFW) profile, and a generalized version of the NFW profile. For the luminous matter distribution, we based the model on the observed light distribution that is fitted with three components: a point mass for the central light component resembling an active galactic nucleus, and the remaining two extended light components scaled by a constant mass-to-light ratio (<i>M<i/>/<i>L<i/>). To constrain the model further, we included published velocity dispersion measurements of the lens galaxy and performed a self-consistent lensing and axisymmetric Jeans dynamical modeling. Our model fits well to the observations including the radial arc, independent of the DM profile. Depending on the DM profile, we get a DM fraction between 60% and 70%. With our composite mass model we find that the radial arc helps to constrain the inner DM distribution of the Cosmic Horseshoe independently of the DM profile
%U https://www.aanda.org/articles/aa/full_html/2019/11/aa35042-19/aa35042-19.html