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arXiv · astro-ph/0501324

Gravitational Imaging of CDM Substructure

L. V. E. Koopmans
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Abstract

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 M_sub~10^-3 M_lens, 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 ground-based direct-detection experiments, and probe the hierarchical structure-formation model which predicts this substructure to exist in great abundance.

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L. V. E. Koopmans. 2005-08-17. Gravitational Imaging of CDM Substructure. https://doi.org/10.1111/j.1365-2966.2005.09523.x

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