Galaxy clusters as largest well defined objects can be used to test cosmological model parameters and to explore the cosmic large-scale structure.
Based on the largest well understood sample of galaxy clusters selected by their X-ray luminosity in the ROSAT All-Sky survey we obtain a precise characterization of
the galaxy cluster population in the nearby Universe out to redshifts of about 0.4. Using the X-ray luminosity function we get new tight constraints on the cosmological parameters for the matter density and the amplitude of the large-scale structure density fluctuations. Our results are in good agreement with the recent results from galaxy clusters detected in the PLANCK Mission. We also use the clusters to explore the large-scale structure in the nearby Universe. We constructed a catalog of supercluster systems as mass
concentrations that will likely collapse in the future and show some of their properties. We also have detected a pronounced nearby void region in the southern sky with a size of about 250 Mpc which has also been traced by galaxies.
Event dates: Thursday, 19 June, 2014 - 15:00 - 17:00
Reports:
"Cosmological studies with X-ray galaxy clusters"