14 April 2021Séminaire – François Mernier (ESA/ESTEC)

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From stars to large-scale structures: chemical enrichment in the intracluster medium

Despite being the building blocks of rocky planets and even life, metals mostly reside outside galaxies – i.e. within a hot, ionized, X-ray emitting plasma pervading galaxy clusters and groups, and massive ellipticals. The presence of these metals in such volumes constitutes thus a fossil record of the enrichment of the largest-scale structures of our Universe, and measuring the abundance of their chemical elements (via X-ray spectroscopy) in these systems is the key to understand when, where, and by which physical processes this large-scale enrichment took place. Moreover, the accuracy on specific abundance ratios offered by the most recent generation of X-ray observatories allows us to put constraints on the physics and environment of the (Type Ia and core-collapse) supernovae responsible for the enrichment at cluster scales. Here we will briefly review the most recent achievements in this field (mainly obtained with XMM-Newton, Suzaku, and Hitomi), before showing how high-resolution spectroscopy offered by future missions – in particular Athena – will push our understanding of the cycle of baryons and metals to the next level.