Gas Clumping in the Outskirts of Lambda-CDM Clusters

Understand

Recent Suzaku X-ray observations revealed that the observed entropy profile of the intracluster medium (ICM) deviates significantly from the prediction of hydrodynamical simulations of galaxy clusters.

• In this work, we show that gas clumping introduces significant biases in X-ray measurements of the ICM profiles in the outskirts of galaxy clusters.
• Using hydrodynamical simulations of galaxy cluster formation in a concordance Lambda-CDM model, we demonstrate that gas clumping leads to an overestimate of the observed gas density and causes flattening of the entropy profile.
• Our results suggest that gas clumping must be taken into account when interpreting X-ray measurements of cluster outskirts.