Séminaires : Documents

Probing dark matter in galactic scales with gravitational lensing
Georgios Vernardos (University of Groningen)

The tension between dark matter theory and observations that exists in sub-galactic scales has given rise to challenging problems, among which the infamous `missing satellites’ and `cusp-core’ problems. Gravitational lensing is a unique tool to address these problems due to its ability to detect dark matter properties and its connection to baryons at cosmological distances. I will present recent advances in the gravitational imaging technique – a method used to reconstruct the lensing potential and the source brightness profile from strong lensing features in observed lenses, like arcs and rings. In particular, a new, general, and powerful statistical treatment will be introduced, which enables the coherent study of small scale dark matter perturbations, or higher order moments in the global lens potential, allowing for a simultaneous derivation of their degeneracies for the first time. An initial application to a few simulated lens systems will be presented as well.