Lensing Optical Depths for Substructure and Isolated Dark Matter Halos

  title={Lensing Optical Depths for Substructure and Isolated Dark Matter Halos},
  author={Jacqueline Chen and Andrey V. Kravtsov and Charles R. Keeton},
  journal={The Astrophysical Journal},
Multiply imaged quasar lenses can be used to constrain the substructure mass fraction in galaxy-sized dark matter halos via anomalous flux ratios in lensed images. The flux ratios, however, can be affected both by the substructure in the lens halo and by isolated small-mass halos along the entire line of sight to the lensed source. While lensing by dark matter clumps near the lens galaxy is more efficient than elsewhere, the cumulative effect of all objects along the line of sight could be… Expand

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