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Paper: |
Modeling the Double Source-Plane Gravitational
Lens |
Volume: |
446, Galaxy Evolution: Infrared to Millimeter Wavelength Perspective |
Page: |
137 |
Authors: |
Tu, H.; Gavazzi, R.; Limousin, M.; Cabanac, R.; Marshall, P. J.; Fort, B.; Treu, T.; Péllo, R.; Jullo, E.; Kneib, J.-P.; Sygnet, J.-F. |
Abstract: |
SL2SJ02176-0513 is a remarkable lens for the presence of two multiply-imaged
systems at different redshifts lensed by a foreground massive galaxy
at ɀlens = 0.656: a bright cusp arc at ɀarc = 1.847 and an additional
double-image system at an estimated redshift of ɀdbl∼2.9 based
on photometry and lensing geometry. The system is located about
400 kpc away from the centre of a massive group of galaxies. Mass
estimates for the group are available from X-ray observations and
satellite kinematics. Multicolour photometry provides an estimate of
the stellar mass of the main lens galaxy. The lensing galaxy is
modelled with two components (stars and dark matter), and we include
the perturbing effect of the group environment and all available
constraints.
We find that classic lensing degeneracies, are significantly reduced with
respect to standard systems and infer tight constraints on the mass
density profile: (i) the dark matter content of the main lens galaxy
is in line with that of typical galaxies ƒdm(< Re) = 0.41–0.06+0.09; (ii) the required mass
associated with the dark matter halo of the nearby group is
consistent with X-ray (σgrp = 550–240+130);
(iii) accounting for the group contribution in the form of an external
convergence, the slope of the mass density profile of the main lens
galaxy alone is found to be α = –1.03–0.16+0.22,
consistent with the isothermal (α = –1) slope. |
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