Warning: following the coronavirus emergency, all the talks will be given remotely online. The link to connect to the seminar will be available in due time. A playlist of the remote talks already online is available on our YouTube channel »
Improving galaxy cluster strong lensing models using internal kinematics of cluster member galaxies.
Pietro Bergamini (INAF-OAS)
Tuesday 30/06/2020 @ 14:00, Google Hangouts Meet
Galaxy clusters are important astrophysical laboratories to study the nature of Dark Matter (DM), whose physical properties are still unknown. In particular, a detailed investigation of the mass distribution of cluster halos, by dissecting the DM and baryonic components, can provide stringent tests of the $\Lambda$ Cold Dark Matter paradigm of structure formation. Over the last decade, strong gravitational lensing has become the most powerful technique to study the total mass distribution of the inner region of galaxy clusters. Observations of galaxy clusters with the integral-field spectrograph MUSE (Multi-Unit Spectroscopic Explorer) on the VLT, in combination with HST multi-band imaging programs, have been critical for the development of a new generation of high-precision strong lensing models, via the identification of a large number of spectroscopic multiple images and cluster member galaxies. Moreover, by enabling the measurement of the internal velocity dispersion of a large fraction of early-type cluster members, MUSE allows us to compare kinematical properties of the cluster sub-halo population with those derived from the strong lensing models. Our study focuses on three massive clusters MACS~J1206.2$-$0847, MACS~J0416.1$-$2403, and Abell S1063 at $z\sim 0.4$ with HST imaging and VLT spectroscopy.
Link to the recorded talk: youtu.be/FKeU85aZl3o