English

Gravitational Imaging of CDM Substructure

Astrophysics 2015-06-24 v3

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.

Keywords

Cite

@article{arxiv.astro-ph/0501324,
  title  = {Gravitational Imaging of CDM Substructure},
  author = {L. V. E. Koopmans},
  journal= {arXiv preprint arXiv:astro-ph/0501324},
  year   = {2015}
}

Comments

11 pages, 4 figures; Accepted for publication in MNRAS

R2 v1 2026-07-22T08:47:35.073Z