We will introduce the importance and the challenges of detecting and studying clusters and protoclusters at z>1.5. In particular, we will focus on results obtained on a sample of clusters and protoclusters detected by the Cluster Around Radio Loud AGN survey (CARLA), and discuss their implication for future surveys with combined observations from Euclid and LSST. The analysis of CARLA spectroscopically confirmed clusters at 1.3<z<2.8 shows that the morphology-density and passivity-density relations are already in place at z~2, with high fractions of ETG observed at z~3. We observe large percentages of active ETG at z~2, and mergers and asymmetry are significantly higher in these clusters compared to the field. We will discuss the molecular and hot gas content of some clusters in our sample. Finally, we will present recent predictions for Euclid detections using semi-analytical and empirical models.
Local contat & organization: Emanuele DADDI
