[Previous] | [Session 80] | [Next]

[80.03] Gravitational Lensing by Galactic Substructure and the Nature of Dark Matter

R.B. Metcalf (University of California Santa Cruz)

Observations of multiply--imaged quasars at high redshift have been used to probe dark matter clumps within the lensing halos. A large abundance of such invisible satellites is predicted by the cold dark matter (CDM) model while in warm dark matter or interacting dark matter models they are rare or absent. Numerical lensing simulations show that the quasar magnification ratios and the relative shapes of quasar radio jets are strongly affected by substructure. We find that smooth halo models containing no substructure are not compatible with a variety of lensing observations.

[Previous] | [Session 80] | [Next]

Bulletin of the American Astronomical Society, 34, #4
© 2002. The American Astronomical Soceity.