Gravitational Imaging of CDM Substructure
نویسنده
چکیده
We propose the novel method of “gravitational imaging” to detect and quantify luminous and dark-matter substructure in gravitational-lens galaxies. The method utilizes highly-magnified Einstein rings and arcs as sensitive probes of small perturbations in the lens potential (due to the presence of mass substructure), reconstructing the gravitational lens potential non-parametrically. Numerical simulations show that the implemented algorithm can reconstruct the smooth mass distribution of a typical lens galaxy – exhibiting reasonable signal-to-noise Einstein rings – as well as compact substructure with masses as low as Msub∼10 −3 Mlens, if present. “Gravitational imaging” of pure dark-matter substructure around massive galaxies can provide a new window on the standard cold-dark-matter paradigm, using very different physics than groundbased direct-detection experiments, and probe the hierarchical structure-formation model which predicts this substructure to exist in great abundance.
منابع مشابه
Gravitational-Mass Imaging of CDM Substructure
I propose the novel method of “gravitational-mass imaging” to detect and quantify luminous and dark-matter substructure in gravitational-lens galaxies. The method utilizes highly-magnified Einstein rings and arcs as sensitive probes of small perturbations in the lens potential (due to the presence of mass substructure), reconstructing the gravitational lens potential non-parametrically. Simulat...
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