Speaker
Prof.
Piero Rosati
(Universita' di Ferrara)
Description
abstract: Galaxy clusters are a powerful tools to test the Lambda-Cold-Dark-Matter (LCDM) cosmological paradigm and the structure formation scenario. Their multi-wavelength study reveal key information on the dark sector of the Universe (DM and dark energy), as well as on the cosmic circulation of baryons in the cold and hot phase. I will briefly review the methodologies and recent results in this field. I will then describe an on-going project (called CLASH), which combines an Hubble treasury program with a large spectroscopic survey with the VLT to study the mass distribution (dark matter and baryons) of 25 clusters at intermediate redshift with unprecedented accuracy, using gravitational lensing and kinematics techniques. I will describe the potential of these observations to shed light on the nature of the DM. These massive clusters also act as powerful gravitational telescopes, magnifying the most distant galaxies which would otherwise escape detection, thus allowing us to search for the first stars well into the first billion year of cosmic history.
