Seminar Series

A SHARP View of Dark Matter in Distant Galaxies

Chris Fassnacht, UC Davis

19 Feb 2015 - 15:30

In this talk I will show how the powerful combination of gravitational lensing and sensitive, high-resolution imaging can provide direct observational tests of galaxy formation scenarios under the cold dark matter paradigm. In particular, I will discuss how we can use the technique of "gravitational imaging" to place observational constraints on the mass function of substructure in galaxy-scale dark matter halos.  With this method we are, for the first time, directly measuring masses of galaxy satellites well outside of the Local Group.  These measurements can be made even if the satellites are composed purely of dark matter, and provide an excellent complement to information obtained from investigations of Milky Way satellite galaxies.  The imaging used for the project that I will discuss comes from Keck adaptive optics (AO) and Hubble Space Telescope (HST) observations.  In some cases the AO imaging is clearly sharper than that obtained with HST.


LCO Seminar Series,
6740 Cortona Dr, Suite 102,
Goleta, CA 93117