B18 - Studies of the Dark Universe with eROSITA Galaxy Clusters

Principal Investigators: H. Böhringer (Garching); J. Mohr (Munich); T.H. Reiprich (Bonn)


Galaxy clusters are ideal probes for the cosmic large-scale structure and for the test of cosmological models. Observationally, X-ray observations have so far been found to provide one of the cleanest galaxy cluster selection methods for cosmological studies. The forthcoming survey with the eROSITA instrument on the Spektrum-Roentgen-Gamma satellite is the most promising project in the near future to test cosmological models through the comparison of the observed evolution of structure in the Universe with the prediction of theoretical models. These studies will be based on tens of thousands of X-ray selected galaxy clusters that will be discovered in the survey, increasing the number of galaxy clusters by almost two orders of magnitude over previous X-ray studies. Moreover, using the deep multi-band optical Dark Energy Survey (DES) we can constrain the masses of these X-ray selected systems using weak lensing shear. We will trace the evolution of structure with eROSITA clusters between now and redshifts up to 1 - 1.5. These cosmological constraints obtained from this cluster survey are complementary to those of other observational probes of cosmology applied in the TR33 project.