Cosmology Results from the First eROSITA All-Sky Cluster Survey

Clusters of galaxies trace the highest peaks in the cosmic density field and offer an independent and powerful probe of the growth of structure and cosmology. Successfully launched in July 2019, eROSITA, the German-built telescope array operating between 0.2-8 keV on board the Russian-German Spectrum-RG (SRG) mission delivers the largest catalogs of clusters of galaxies from its All-Sky Surveys. The first results from the performance verification program have confirmed that eROSITA will detect the predicted number of clusters of galaxies and fulfil its promise in cosmology. The first eROSITA all-sky survey, yielding more than 10,000 confirmed clusters of galaxies, constrains the cosmological parameters from cluster mass function and cluster-clustering when combined with the overlapping DES, HSC, and KIDS weak lensing surveys. I will summarize the first results on cluster science and cosmology from the eROSITA’s first All-Sky Survey and provide an outlook for the future deeper surveys.