Multi-wavelength Cluster Cosmology

In this project, we will approach two major challenges to the standard cosmological model: what is responsible for the late time acceleration of the expansion of the Universe, and what is the nature of dark matter. X-ray observations of clusters of galaxies will be at the core of our activity. In most cases, access to Optical/near-IR imaging surveys will also be essential. Some of the necessary data sets are already at our disposal (thanks to our previous work on the XMM Cluster Survey, XCS, and the Dark Energy Survey, DES). Others will become available during the duration of the project (thanks to the eROSITA All Sky Survey, eRASS, and the Legacy Survey of Space and Time, LSST). The project will involve X-ray support to the extraction of cosmological parameters from clusters detected by DES and LSST and testing modified gravity models through the differing responses of the ICM and the DM to a ``fifth force''.