We measure stellar velocities in the nuclei of galaxies with SINFONI, and model them to constrain the masses of the nuclear black holes. In this context, we adress the following questions in particular: Where do these giant black holes come from? What are their seeds? How do they grow?[more]
We determine the dark matter distribution in elliptical galaxies through dynamical modeling. Furthermore, we weigh dark matter halos through their lensing effect. We also analyze the lensing effect of clusters of galaxies and large scale structure.
We are executing surveys to measure the power spectrum of the galaxy distributions at high redshifts (z = 1-2) as a tool to constrain the redshift evolution of the equation of state of Dark Energy.
We design and build instruments for ESO, the HET telescope, the Wendelstein Observatory. We develop software for the HETDEX experiment, the PanSTARRS1 project. We participate to the proposal for ESA EUCLID satellite mission.