TY - JOUR
T1 - Inner dark matter distribution of the Cosmic Horseshoe (J1148+1930) with gravitational lensing and dynamics
AU - Schuldt, S.
AU - Chirivì, G.
AU - Suyu, S. H.
AU - Ylldlrlm, A.
AU - Sonnenfeld, A.
AU - Halkola, A.
AU - Lewis, G. F.
N1 - Publisher Copyright:
© S. Schuldt et al..
PY - 2019/11/1
Y1 - 2019/11/1
N2 - We present a detailed analysis of the inner mass structure of the Cosmic Horseshoe (J1148+1930) strong gravitational lens system observed with the Hubble 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 zs,r = 1.961 ± 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 (M/L). 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.
AB - We present a detailed analysis of the inner mass structure of the Cosmic Horseshoe (J1148+1930) strong gravitational lens system observed with the Hubble 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 zs,r = 1.961 ± 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 (M/L). 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.
KW - Dark matter
KW - Galaxy: halo
KW - Galaxy: kinematics and dynamics
KW - Galaxy: structure
KW - Gravitational lensing: strong
UR - http://www.scopus.com/inward/record.url?scp=85074449964&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/201935042
DO - 10.1051/0004-6361/201935042
M3 - Article
AN - SCOPUS:85074449964
SN - 0004-6361
VL - 631
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
M1 - A40
ER -